Health Protection Agency
North East and North Central London HPU
JOINT INFECTIOUS DISEASE
PROTOCOL
London Boroughs of Barking & Dagenham, Barnet, Camden,
Enfield, Hackney, Haringey, Havering, Islington, Redbridge,
Newham, Tower Hamlets, Waltham Forest and the City of
London
Current version V2.2
This document was reviewed by Maria Saavedra-Campos, Katie Fleet, Sarah Addiman, Erika Huszar
and the EHOs of the EHDs above
North East and North Central London HPU
JOINT INFECTIOUS DISEASE PROTOCOL
Revised September 2011
OCUMENT NAME
FILE LOCATION
FOR USE BY
JOINT INFECTIOUS DISEASE PROTOCOL
DOCUMENT STATUS
CURRENT VERSION
ISSUE NUMBER AND DATE
Final plan document
V2.2 September 2012
V2. September 2011
V2.1 January 2012
April 2006: V1.
Author: Sarah Addiman
AUTHORS
Health Protection Agency. London
NENC Local Authorities (Environmental Health Officer)
September 2011: V2.1
Revision – Maria Saavedra-Campos, Katie Fleet, Sarah
Addiman, Erika Huszar
September 2012: V2.2
Reviewed by Maria Saavedra-Campos
- 9.3 section added management of sporadic cases of
campylobacter and salmonella spp. & updated
actions table
- Updated version of London Outbreak Plan
- Shigella questionnaire
OTHER CONTRIBUTORS
CONSULTATION
(September 2011)
North East North Central London HPU
EHOs Local Authorities in North East North Central Sector
ACCREDITATION AND
ENDORSEMENT
NENC London HPU
Environmental Health Departments North East & North
Central London Sector
REVIEW DATE
September 2013
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Contents
1. INTRODUCTION ......................................................................................... 4
2. AIMS OF THE INVESTIGATION OF INFECTIOUS DISEASES OR
CONTAMINATION ........................................................................................... 5
3. SURVEILLANCE.......................................................................................... 5
4. COMMUNICATION OF SPORADIC CASES OF INFECTIOUS DISEASES 5
5. COMMUNICATION OF LINKED CASES, CLUSTERS OR SMALL
OUTBREAKS ................................................................................................... 6
6. MAJOR OUTBREAKS ................................................................................. 7
7. COMMUNICATION OF CROSS BOUNDARY CASES OF INFECTIOUS
DISEASES ....................................................................................................... 8
8. COMMUNICATION OF SITUATIONS WHERE CONTAMINATION IS
IDENTIFIED ..................................................................................................... 8
9. MANAGEMENT OF ROUTINE SPORADIC CASES ................................. 14
9.1 INTRODUCTION ............................................................................................. 14
9.2 RISK ASSESSMENT ........................................................................................ 14
9.3 MANAGEMENT OF SPORADIC CASES OF CAMPYLOBACTER AND
SALMONELLA SPP NON TYPHOID OR PARATYPHOID ............................... 15
9.4 MINIMUM AGREED ACTIONS ..................................................................... 16
9.5 FURTHER INVESTIGATION ......................................................................... 17
9.6 SPECIMEN COLLECTION .............................................................................. 17
9.7 CONTROL......................................................................................................... 18
9.7.1 General advice ............................................................................................ 18
9.7.2 General advice in relation to gastrointestinal disease ................................. 19
10. DEALING WITH SINGLE URGENT CASES ............................................ 19
11. REFERENCES ........................................................................................ 21
Appendix 1a – Disease Information ............................................................... 22
Appendix 1b – Toxins .................................................................................... 60
Appendix 1c – Factsheets, links and policies ................................................. 71
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JOINT INFECTIOUS DISEASE PROTOCOL
1. INTRODUCTION
Significant changes to Legislation as outlined by the Health Protection
Legislation (England) Guidance 2010 (Appendix 1c) have encouraged the
revision of the 2006 Joint infectious disease protocol.
The document is intended for use as an initial guide, to supplement
management of individual cases of infection and complement existing “inhouse” procedures. Thus fulfilling the agreement laid out in the joint
Memorandum of Understanding.
In some cases it will be necessary to refer to supplementary detailed
guidance. Where this is the case this has been indicated in the text.
This document summarises the working arrangements between the North
East and North Central London Health Protection Unit (NENCL-HPU) and the
Environmental Health Departments (EHD) of the Local Authorities (LA) in the
sector regarding the investigation and communication of infectious diseases.
The document includes relevant organisms that might not necessarily be
notifiable according to the Health Protection Legislation (England) Guidance
2010 but that might pose a public health risk. The guidance explains the
requirements on registered medical practitioners to notify cases of infectious
disease or contamination (chemicals or radiation) that present a significant
risk to human health and the requirements on diagnostic laboratories to notify
the Health Protection Agency (HPA) of specified causative agents. Note that
the focus of the document is on infectious diseases and notifications of
organisms. However, communication arrangements regarding contamination
notifications have been included as this has now been included in the new
legislation.
The document illustrates:




how the two departments will communicate depending on the urgency of
the diseases/organisms or contamination notified
roles and responsibilities and clarification on who will be leading the
investigations of specific diseases, situation or outbreaks
a list of minimum actions required for sporadic cases of food-borne
pathogens
surveillance outputs that they HPU will provide on a regular basis
This is based on previous agreement in the Joint Infectious Disease Protocol
(2006) and EHD forums, new health protection legislation (2010) and ongoing
organisational changes in both, NENCL-HPU and EHDs.
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2. AIMS OF THE INVESTIGATION OF INFECTIOUS
DISEASES OR CONTAMINATION
 To prevent the spread of infection or further exposure to a
contaminant and to reduce the number of cases of illness;
 To ensure the prompt recognition and identification of the source of
the infection or contamination;
 To initiate appropriate action and provide any advice and education
which
is
necessary
to
control
the
source
of
the
infection/contamination and to prevent a recurrence
3. SURVEILLANCE
The HPU will continue to produce weekly, monthly and annual reports that will
be circulated to the EHDs by email.

The weekly reports will include cases, incidents and outbreaks in the
sector notified to the NENCL HPU and for which the investigation was
primarily lead by the HPU. This report is produced from HPZone data
and does not currently include laboratory notifications forwarded
directly from the HPU to EHDs for action

The monthly report includes all cases, incidents and outbreaks notified
to the NENCL HPU and entered on HPZone. It also includes some
comparisons with previous years. It is planned that monthly reports will
also include laboratory data, mainly including infections for which the
investigation is primarily lead by the EHDs i.e. campylobacter

An annual report will also be produced and distributed to the EHDs in
the sector. This will include data from both data sources HPZone and
lab data.
None of these reports will contain personal identifiable information (PII). The
reports provide an overview of the activity in the sector.
Enhanced surveillance will continue to be routinely required for certain
diseases (e.g. Listeria). This may take the form of a national enhanced
surveillance questionnaire e.g. Legionella, enteric fever or it may be specific
to certain infectious diseases in the event of an increased in the national
incidence e.g. Salmonella spp. There may also be occasions where the EHD
and HPU have agreed to carry out local enhanced surveillance for a particular
communicable disease.
4. COMMUNICATION OF SPORADIC CASES OF
INFECTIOUS DISEASES
The document contains two tables with a list of relevant diseases, organisms
and syndromes or clinical presentations. Note that table 1 and 2 refer to
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sporadic cases. Table 1 is organised alphabetically by disease. The tables
contain how quickly the information should be passed between departments
as agreed between EHDs and NECL HPU in July 2010. The tables also
provide information on who leads the investigation i.e. HPU, EHD or joint. For
the purpose of communication it was agreed that urgent cases should be
communicated on the same day. Urgency would be determined by the
following:
o diseases for which immediate action is needed to ensure that
appropriate public health actions are instigated e.g. enteric fever
o diseases that fall within the remit of joint working between EHDs
and HPU team before investigations and control are agreed (Table
1 and 2)
o diseases that might attract significant media attention e.g. anthrax,
Viral haemorrhagic fever
o diseases for which the EHDs lead the investigation and early
intervention is necessary to prevent further exposure e.g. food
poisoning link to a particular establishment
Some diseases and organisms are associated with major concerns, even if
they are sporadic cases, in this instance communication between
departments should happen immediately. For urgent notifications
communication would be on the same day the notification is received. As
specialist assessment is required to be undertaken by the EHD and the HPU
it is essential that notification of urgent cases is communicated early.
NENCL HPU will forward lab reports of notifiable infections requiring routine
EHD action via encrypted email on a “next working day” basis (via fax for EHD
Hackney until the encrypted system is set up). Note that urgent cases will be
called through for discussion and to agree further actions. Documentation
related to urgent cases i.e. questionnaires, potting schedules would be sent
via encrypted email (via fax for EHD Hackney until encrypted system is set
up) unless advise otherwise. Note that email addresses will be kept in the
contact lists folder. It is the responsibility of both organisations to keep each
other informed of any changes to email addresses or contact numbers so
prompt communication and continuity of service can be maintained.
Note that for conditions not covered or where there is any uncertainty both
organisations should consult each other as a matter of urgency to determine
whether further action is required and to agree roles and responsibilities.
5. COMMUNICATION OF LINKED CASES, CLUSTERS
OR SMALL OUTBREAKS
For diseases not circulating in the community, an outbreak is two or more
persons with the same disease or the same organism isolated from a
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diagnostic sample, or who are linked through common exposure, personal
characteristics, time or location.
For diseases circulating in the community, an outbreak is a greater than
expected rate of infection compared with the usual background rate for that
particular place or time.
The commonest diseases, which give rise to an outbreak, are gastro-intestinal
infections (bacterial or viral). Sometimes a single case of certain diseases
such as Diphtheria, rabies or Viral hemorrhagic fever, where there is an
immediate or serious health hazard to the population of a Health/Local
Authority (LA) may be managed as an outbreak.
When organisations become aware of a potential outbreak they should
immediately communicate with each other.
Environmental Health Department initial action

EHDs becoming aware of outbreaks should ring NENCL - HPU and speak
directly with the on-call team.

EHDs will then implement actions specified in their own in-house
procedures and work instructions.
HPU team initial action

If the HPU team are informed first (for example by GP or microbiologist)
they should ring the relevant EHD immediately.

Allocate a person or team to respond
Circumstances will dictate how an episode will be recognised by the HPU and
there may be difficulty in deciding when to declare that a significant outbreak
has occurred. Suspicions may be aroused as a result of increases in
notifications of infectious disease and/or laboratory reports as well as on
information received from Hospital Consultants, GPs, EHOs, Water Company
representatives, members of the public, etc. Revision of surveillance data and
trends will assist on making this decision. The HPU will seek advice from the
Regional Epidemiologist or from the Microbiology services as appropriate.
The principles and procedures of the outbreak response are included in the
London Infectious Disease Outbreak Management Plan (Appendix 1c).
6. MAJOR OUTBREAKS
A more serious outbreak may be an outbreak where there are a large number
of cases or one where the illness is severe, such as to require hospitalisation.
Major outbreaks may require EHDs and/or HPU Incident and Emergency plan
to be activated. The incident will be managed by an outbreak control team
with similar composition as for smaller outbreaks. However, representatives
from other geographical areas and specialist advisers are likely to be
required.
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Sufficient office accommodation and administrative support is needed. This
may need to be within a major incident room (either at a LA, NENCL-HPU
office or a local Public Health Department site).
7. COMMUNICATION OF CROSS BOUNDARY CASES
OF INFECTIOUS DISEASES
This refers to cases for which initial investigations show that possible sources
of infection or exposures are identified in different LA e.g. food poisoning
cases link to several food establishments.
In this cases if the exposure or possible sources are located within North East
and Central London
o Initial report is received by the HPU: the information will be relayed to
the appropriate EHDs by the HPU
o Initial report is received by the EHDs: the information will be relayed to
the appropriate EHDs by the EHD receiving the report and also to the
HPU.
If the exposure or possible sources are located outside North East and
Central London:
o Initial report is received by NENCL HPU the information will be passed
to the appropriate HPU
o Initial report is received by EHD in the sector details will be passed to
NECL HPU for referral to the appropriate HPU and subsequently the
appropriate EHD. The EHD receiving the notification first, might alert all
the appropriate colleagues. However, if this is not done it should be
discussed with the HPU and a communication strategy agreed to
ensure all relevant organisations are informed.
Note that this only reflects the pathway of communication between different
departments, for urgent cases all departments involved in the investigation
should be aware of all the different lines of investigation. For urgent cases
there is likely to be a questionnaire that will enclose all this information and
that should be shared between all the departments involved e.g. E. coli O157,
enteric fever, Legionella
8. COMMUNICATION OF SITUATIONS WHERE
CONTAMINATION IS IDENTIFIED
Both departments should ensure prompt communication in any situation or
incident where exposure to chemicals or radiation is identified. Even in
situations where the public health implications are not considered to be
significant both departments should alert each other. This could be done via
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email if the situation is not assessed as urgent or not needing further actions.
Emails to the HPU should be sent to the team email as below:
necl.team@hpa.org.uk
As the on call team changes on a daily basis; to ensure that communications
are not missed EHO should add the team email address when they
communicate a new situation to the unit. Otherwise they can communicate
using the office number and by talking to a member of the on call team.
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Table 1: list of organisms and diseases, communication and organisation leading investigation for sporadic cases
Disease
Acute encephalitis
Acute meningitis (viral &
bacterial)
Acute poliomyelitis
Acute Hepatitis A & E
Organism
Neisseria meningitidis,
Sterptococcus pneumonia,
Haemophilus Influenzae
Polio virus
Hepatitis A & E virus
Communication
between HPU & EHD
Actions lead by
Weekly report
Weekly report
HPU action only
HPU action only
Weekly report
Same day
HPU action only
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU action only (unless implications for EHD)
Acute Hepatitis B & C &
Delta
Anthrax
Hepatitis B, C & Delta
Bacillus anthracis
Weekly report (unless
actions for EHD)
Same day
Botulism
Clostridium botulinum
Routine
Brucellosis
Brucella spp (Same dayif UK
acquired)
Chikungunya
Cholera
Cryptosporidiosis
Diphtheria
Chikungunya virus
Vibrio cholerae
Cryptosporidium spp
Corynobacterium diphtheriae
Corynobacterium ulcerans
Salmonella typhoid Salmonella
paratyphoid
Bacillus cereus Campylobacter spp,
clostridium perfringes,
Staphylococcus aureus
(enterotoxin- strains) Norovirus,
Scrombotoxin
Same day(if UK
acquired otherwise
routine)
Weekly report
Same day
Routine
Weekly report
Enteric fever (typhoid or
paratyphoid fever)
Food Poisoning (any
disease of infectious or
toxic nature caused by, or
thought to be caused by
consumption of food or
water)
Same day
Same day
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU lead, discuss with EHO to agree investigation
and control as necessary
HPU action only
HPU lead
EHO lead, discuss with HPU
HPU action only
HPU lead, discuss with EHD to agree investigation
and control as necessary
EHO lead, discuss with HPU to agree investigation
and control as necessary
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Disease
Organism
Giardiasis
Glander & mieloidosis
Giardia Lamblia
Burkholderia mallei Burkholderia
pseudomallei
Streptococcal pyogenes
Invasive group A
streptococcal disease &
scarlet fever
Communication
between HPU & EHD
Routine
Weekly report
Actions lead by
Weekly report
HPU action only
Same day
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU action only
EHD lead, discuss with HPU to agree investigation
and control as necessary
EHD lead
HPU action only
Legionella
Legionella spp
Leprosy
Leptospirosis
Leptospira interrogans
Listeria
Listeria monocytogenes
Weekly report
Weekly report (unless
EHO involvement is
needed)
Same day
Lyme disease
Borrelia spp
Weekly report
Malaria
Weekly report
Weekly report
HPU action only
Meningococcal disease
Plague
Plasmodium falciparum, vivax,
ovale, malariae and knowlesi
Measles virus, Mumps virus and
Rubella virus
Neisseria meningitidis
Yersinia pestis
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU action only
Weekly report
Same day
Psittacosis
Q-fever
Rabies
Chlamydophila psittaci
Coxiella burnetii
Rabies virus
Weekly report
Weekly report
Weekly report
HPU action only
HPU lead, discuss with EHD to agree investigation
and control as necessary
HPU action only
HPU action only
HPU lead, discuss with EHD to agree investigation
and control as necessary
Measles, Mumps, Rubella
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Disease
Organism
Communication
between HPU & EHD
Weekly report
Actions lead by
Relapsing fever
Borrelia spp
Salmonellosis (not typhoid
or paratyphoid)
Sever acute respiratory
syndrome (SARS)
Shigellosis
Salmonella spp (not typhoid or
paratyphoid)
Coronavirus
Routine
EHO lead
Weekly report
HPU action only
Shigella sonnei
Routine
EHD lead
S. boydii, S. dysenteriae, and
S.flexneri
Same day
HPU lead, discuss with EHD to agree investigation
and control as necessary
Smallpox
Taenia solium (worms)
Tetanus
TB (note only incidents
would be reported)
Typhus
Viral haemorrhagic fever
Variola virus
Taenia solium (worms)
Clostridium tetani
Same day
Same day
Weekly report
Weekly report
HPU action only
EHO lead
HPU action only
HPU action only
Rickettsia spp
Crimean-Congo haemorrhagic fever
virus, Guanarito virus, Hanta virus,
Junin virus, Kyasanur Forest
disease virus, Lassa virus, Machupo
virus Marburg virus, Omsk
haemorrhagic fever virus, Rift Valley
fever virus and Sabia virus
Weekly report
Same day
HPU action only
HPU lead, discuss with EHD to agree investigation
and control as necessary
VTEC including O157
Verocytotoxigenic Escherichia coli
(VTEC) including E. coli O157
Bordetella pertussis
Yellow fever virus
Same day if E. coli
O157
Weekly report
Weekly report
HPU lead, discuss with EHD to agree
investigation and control as necessary
HPU action only
HPU action only
Whooping Cough
Yellow Fever
HPU action only
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Table 2: Notifiable syndromes or clinical presentations, communication with EHDs and organisation leading for sporadic cases
Notifiable syndromes or clinical
presentations
Communication between HPU & EHD
Actions lead by
Haemolytic uraemic syndrome (HUS)
Weekly report (Same day only if actions
for EHO identified)
HPU lead, discuss with EHD to agree investigation and
control as necessary
Infectious bloody diarrhoea
Weekly report (Same day only if actions
for EHO identified)
HPU Lead, discuss with EHD to agree investigation and
control as necessary
Table 3: Notification of contamination incidents, communication between departments and organisation leading initial response
Notification of contamination
Communication between HPU & EHD
Actions lead by
Exposure to chemicals
Same day
HPU lead, discuss with EHD to agree investigation and
control as necessary (depending on the incident it might be
decided for EHD to lead the investigation)
Exposure to radiation
Same day
HPU Lead, discuss with EHD to agree investigation and
control as necessary (depending on the incident it might be
decided for EHD to lead to lead the investigation)
Communication definitions
Same day: communications with EHO should be on the same day the case is notified.
Routine: will be communicated next working day, via encrypted email as it will contain patient identifiable information (PII).
Weekly report: will include all cases and incidents reported to and managed by the HPU on-call desk for which EH investigations
are not necessarily required e.g. acute encephalitis, meningitis. This report will not contain PII. Note that cases in this report
requiring actions from the EHD would have been already reported via the two methods explained above.
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9. MANAGEMENT OF ROUTINE SPORADIC CASES
9.1 INTRODUCTION
Most of this section deals with routine work considerations, although the principles
apply for dealing with any infectious disease cases. Conditions covered include:

Food Poisoning (notified without a specific cause)

Gastro-enteritis including:
o Campylobacter
o Giardia lamblia
o Salmonella (not Typhoid, Paratyphoid)
o Shigella sonnei
o Viral gastro-enteritis, e.g. Norovirus
o Cryptosporidium
Table 5 indicates the agreed minimum standards for investigation of routine single
cases.
9.2 RISK ASSESSMENT
Public health risk is assessed in terms of continued risk to others. This is in addition
to the health of the individual case.
There are four specific groups of persons in whom it is particularly important to
assess their risk of spreading infection and for whom special action should be
considered.

Groups that pose an increased risk of spreading infection
It is particularly important to assess infected people who belong to one of the four
groups for whom special action should be considered.
Table 4 Risk groups

Group A Any person of doubtful personal hygiene or with unsatisfactory toilet, hand
washing or hand drying facilities at home, work or school.

Group B Children who attend pre-school groups or nursery.

Group C People whose work involves preparing or serving unwrapped foods not
subjected to further heating.

Group D Clinical and social care staff who have direct contact with highly susceptible
patients or persons in whom a gastrointestinal infection would have particularly serious
consequences.
However, the risk assessment should not only be confined to determine whether
cases fit into one of these groups but be based on the organism, the overall lifestyle
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of the cases and their contacts, and the severity of the threat. Risk assessment will
always be a judgement call and requires knowledge and expertise.

People who do NOT pose an increased risk
ALL cases of gastroenteritis should be regarded as potentially infectious and should
normally be excluded, from work, school or other institutional settings, and advised to
refrain from food preparation for others at least until 48 hours after the person is free
from diarrhoea and/or vomiting. For some gastrointestinal infections, as detailed in
the additional policies and CDR Guidance, microbiological clearance may also be
required.
9.3 MANAGEMENT OF SPORADIC CASES OF CAMPYLOBACTER
AND SALMONELLA SPP NON TYPHOID OR PARATYPHOID
A review of the management of sporadic cases of Campylobacter took place in 2011
in order to evaluate the outcome of the investigation of sporadic cases of this
infection. The review followed on a project done by the Regional Epidemiology Unit
to evaluate the delay from clinical diagnosis to public health investigation of the
cases of Salmonella spp not Typhoid or Paratyphoid.
Based on the findings of both reviews, as entered below:
-
significant delay from onset to public health investigations taking place was
observed, reducing the chances of obtaining meaningful information from the
case (from 24 days from onset for a lab notification and 13 from onset for
clinical notifications)
-
very poor response to postal questionnaires, better response to telephone
questionnaires but more resource intensive
-
no evidence of any missed outbreaks
-
anecdotal evidence that outbreaks tend to be identified via the following
routes and not by investigating sporadic cases:
o members of the public
o reports from clinicians
It was agreed in the EHO Forum that EHD were not required to follow every sporadic
case of Campylobacter and Salmonella spp not Typhoid or Paratyphoid. If they were
to do it a telephone questionnaire would be the indicated way. However, this will be a
resource intensive action with uncertain value due to the delay in reporting.
It was agreed that it would be more useful to deploy resources to the investigation of
these cases only when significant increases occurred in a particular area or
particular time that may appear suspicious. The Regional Epidemiology Unit will
review cases in the sector on a weekly basis and alert the unit when increases above
the expected levels are identified. The Unit will communicate with the relevant EHDs
to discuss and agreed if these findings need to be investigated further.
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9.4 MINIMUM AGREED ACTIONS
Table 5 Minimum agreed actions
Minimum EH/HPU Procedures following notifications of potential Food-borne
Pathogens
For single cases (not outbreak or high risk group situations)
Hepatitis A*
Contact ASAP
(Visit or
telephone and/or
clarification with
clinician)
Initial contact –
may be
conducted by
HPU or EHD
HPU
Aeromonas
EHO
Bacillus cereus /
subtilis
EHO
Campylobacter***
EHO
Clostridium
perfringens
EHO
Cryptosporidium
E coli O157*
EHO
1st HPU 2ndEHO
E coli non-VTEC
EHO
Food poisoning
non-specific
Giardia
Salmonella nonTyphoid or
Paratyphoid***
Send appropriate
fact sheet /
advice**
Yes
 (food poisoning
fact sheet)
 (food poisoning
fact sheet)
No need for
sporadic cases
Yes (food
poisoning fact
sheet)
Yes
Yes
Yes (food
poisoning fact
sheet)
Attempt to
clarify by
sending a letter
with
questionnaire
Clearance samples
required
for cases and/or
contacts
See additional
guidance
NO

NO

NO
No need for
sporadic cases
NO

NO


NO


NO
EHO
Yes

NO
EHO
Yes

NO
EHO
No need for
sporadic cases
No need for
sporadic cases
NO
Shigella sonnei
EHO
Yes

NO
Shigella
non-sonnei *
Typhoid &
Paratyphoid
fever*
Taenia solium
(worms)
1st HPU
2nd EHO
Yes
√
√
1st HPU
2nd EHO
Yes


Yes (link to NHS

x
information)
Yes (food
Vibrio non1st HPU
poisoning
fact
NO

cholera
2nd EHO
sheet)
Yes (norovirus or
Viral
EHO
rotavirus fact
NO

gastroenteritis
sheet)
NO
Yersiniosis
HPU
Yes

*These notifications are urgent due to its public health implications. Therefore, all possible efforts
should be made to contact the case or relatives ASAP. If this is not possible by phone a home
visit by the EHO should be organised at the earliest opportunity.
** Copies of the factsheets and links can be found in appendix 1c
*** No need to investigate sporadic cases, only to be investigated if increases are identified by the
Regional Epidemiology Unit (refer to page 15, 9.3 for further information)
EHO
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9.5 FURTHER INVESTIGATION
Note that in outbreak or cluster investigations further information is to be gathered
this should be based on the General Food and Environmental Questionnaire
(Appendix 1c). Please refer to the appropriate policy for more targeted
questionnaires for specific conditions. The questionnaires for specific conditions,
s.typhi/paratyphi, VTEC O157 and Hepatitis A, etc will need to be shared between
HPU and the EHD.
For investigations link to particular events a more targeted questionnaire might need
to be developed. Both departments should discuss the development of more
targeted questionnaires. A final questionnaire will need to be agreed by both parts.
For outbreak situations this discussion is likely to take place during an outbreak
control meeting.
9.6 SPECIMEN COLLECTION
Specimens of stool and vomit form the cornerstone of human gastrointestinal
disease investigation. However, these are only part of the range of investigations
which should be considered. Environment and food samples and NHS samples of
blood and other clinical sites may also be appropriate. Stool tests are not generally
required from suspected routine simple cases e.g Campylobacter, unless there are
concerns about an outbreak or as part of a wider investigation. Vomit samples
should only be submitted after discussion with your local consultant microbiologist.
To get the best possible specimens people should be given the following:

A brief explanation of why samples are needed, how many and at what intervals.

The correct specimen pots and laboratory request forms.

Clear written instructions on how to obtain samples (suitable for people to follow
themselves or for care workers to follow). See Fact Sheet File for fact sheets and
guidelines.

Clear instructions as to when samples will be collected or where they can be
delivered. Ideally, samples should be collected by the EHO.
Barts and the London is the HPA laboratory. The laboratory will provide public health
microbiology services for the Health Protection Units, Environmental Health Officers
(EHOs) and Primary Care Groups across London. This will include the examination
of clinical specimens submitted for the investigation of suspected and confirmed
outbreaks and other incidents of public health importance, excluding those occurring
in hospitals. It is important to note that the Barts and The London will primarily
process clinical samples, while food, water and environmental specimens should be
sent directly to the HPA Food Water & Environmental Laboratory at Colindale.
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Each sector has a named Consultant Microbiologist. They are the first point of call for
all incidents and outbreaks and will be available for advice and direction during
working hours.
Further information on microbiology arrangements can be found in Health Protection
Agency Barts and The London, HPA Laboratory Guidebook for Environmental Health
Officers, Consultants in Communicable Disease Control and Primary Care Groups
(Appendix 1c)
Microbiologist for North Central
London will provide advice to the
following boroughs:
North Central London including
Kensington, Chelsea, Westminster,
Camden, Islington, Barnet and
Haringey
Microbiologist for North East London
will provide advice to the following
boroughs:
North East London including City of
London, Hackney, Tower Hamlets,
Waltham Forest, Barking and
Dagenham, Havering, Redbridge and
Newham
9.7 CONTROL
9.7.1 General advice
The circumstances of each case, excreter, carrier or contact in a risk group should
be considered individually. Amendments to the Health Protection Regulations in
2010 require a change in the way that cases or contacts are advised and requested
to remain away from work/school/nursery for a period of time if needed.
The HPU may only “advise” cases/contacts to remain away from work/school/
nursery or specific activities such as food handling for a period of time as
recommended by policy and guidance in conjunction with individual risk assessment:
 Advise them of the need to remain away in order to prevent possible onward
transmission,
 Advise them to inform their workplace/school/nursery of this advice,
 Give information/fact sheet,
 Advise them that EHO will follow-up next day
 Inform EHO that this information/advice has been given so they can follow-up
next day as necessary
The local authority (usually EHO) may “request” that cases remain away from
work/school nursery or specific activities for a period of time and may instigate
appropriate legal action as necessary if requests are not complied with.
Often formal legal action may not be necessary since unwell patients are able to
remain off work either through self-certification or a certificate from their GP. On
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occasion (sometimes in respect of carriers of organisms who are otherwise well) it
may be decided by the LA and HPU that a lengthy absence from
work/school/nursery or a specific activity is needed, in which case the LA may be
required to pay compensation. Implicated cases or contacts will need to discuss this
directly with the LA involved to explore options available.
With the exception of typhoid, paratyphoid and infections caused by Verocytoxin
producing E.coli (VTEC) O157, shigella dysenteriae, flexneri & boydii, negative stool
samples are not necessary for persons returning to work after a diarrhoeal illness.
See section 10 below, which deals with infections requiring urgent attention.
Some operators of food processes may have their own food handling policies which
cover these situations.
9.7.2 General advice in relation to gastrointestinal disease
Initially all those who are symptomatic should be advised to stay away from their
normal daily activities until 48 hours after they have recovered clinically (but ensuring
that this follows stopping any medication, such as Imodium, which might be masking
symptoms).
The final decision about returning is affected by the type of work or other activity and
by the organism isolated.
Advice will be provided to the case and contacts as relevant either through
conversation when initially contacting the patient and posting information leaflet as
per Table 5.
10. DEALING WITH SINGLE URGENT CASES
When cases of E.coli (VTEC), S.typhi, S.paratyphi, hepatitis A, and shigella
(excluding s.sonnei) are reported there is a need to take immediate action to ensure
the appropriate public health actions can be instigated i.e. assessment and exclusion
of cases and contacts and arrangement for immunisation of contacts as appropriate
(see below for hyperlinks). The response to such cases must therefore be
immediate. This will often require prompt liaison between the EHDs and HPU as the
routes of notification differ i.e. via GPs, Micro, managers etc. Prompt communication
will ensure that an early risk assessment can be conducted and public health risks
can be reduced. This will also ensure that there is a co-ordinated response.
As specialist assessment is required to be undertaken by the EHD and the HPU it is
essential that notification of these cases is communicated early. For example the
response to a case of hepatitis A will require prompt assessment of contacts
requiring immunisation and/or human immunoglobulin as well as identification of
contacts at risk (i.e. in schools, nurseries etc) which will need to assess as early as
possible.
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For conditions not covered in this document or when there is any uncertainty both
Departments should consult each other as a matter of urgency to determine whether
further action is required and agree roles and responsibilities.
Some notifiable diseases, as outlined in Table 1 as the ones that need to be
communicated on the same day, could constitute emergency conditions with
National implications (e.g. Viral Haemorrhagic fever).
If these conditions fall within the remit of joint working between the EHDs and HPU
team then discussion between the two departments should happen as early as
possible. These conditions include:

Potentially complicated gastrointestinal disease, due to risk assessment
required for cases and contacts e.g. VTEC; typhoid and paratyphoid fever,
hepatitis A, shigella and cholera. Please refer to the specific policies below

Other conditions with food or environmental related transmissions such as
leptospirosis and legionnaire’s Disease

Other notified conditions are mainly the remit of clinicians and the HPU team.
Those requiring communication to the HPU by phone or fax on the same day
include: measles; mumps; rubella; scarlet fever and whooping cough or
through written notification reporting e.g. malaria.
The following diseases are considered urgent. Therefore, there are specific policies
for them, which should be referred to:
o Hepatitis A
o Legionella
o Listeria monocytogenes
o Salmonella typhoid and paratyphoid
o Shigella non sonnei
o VTEC O157 (supporting evidence)
Copies of the policies above can be found in Appendix 1c. The policies and guidance
in appendix 1c are the most current ones at the time when this document was
finalised in September 2011. If in any doubt the EHDs should liaise with the HPU to
ensure they have the latest versions. The HPU will communicate any changes in
policies or guidance via the EHO forums and will use the mailing list of the forum to
cascade any relevant information regarding changes to the policies or guidance.
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11. REFERENCES
o Working Group of the former PHLS Advisory Committee on Gastrointestinal
Infections 2004 Preventing person-to-person spread following gastrointestinal
infections: guidelines for public health physicians and environmental health
officers. Commun Dis Public Health 2004; 7(4): 362-384
o The
Health
Protection
(Notification)
Regulations
2010;
http://www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/@dh/@en/@
ps/documents/digitalasset/dh_114589.pdf
o Hawker J, Begg N, Blair I, Reintjes R, Weinberg J 2005 Communicable
Disease Control Handbook. (2nd edition) Blackwell, London
o Guidance on infection control in schools and other childcare settings, Health
Protection Agency, April 2010
o Guidance on Infection Control and Communicable Diseases in Schools,
Colleges and other childcare settings; North East and North Central HPU,
May 2010
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Appendix 1a – Disease Information
Notifiable Disease Information
This section includes brief notes providing disease information. For gastrointestinal
disease the information has been taken from the 2004 Working Group Advisory
Committee on Gastrointestinal Infections (of the former PHLS ).
For other notifiable diseases the information has been compiled from Heyman (2005)
(Control of Communicable Disease Manual), Hawker et al (2005), Communicable
Disease Control Handbook, and the HPA web site.
This section also includes details on chemical food-borne illness. This information
has been taken from the Department of Health 1994 publication on the management
of outbreaks of food-borne illness.
Note that the diseases, for which a specific policy is in place, might not appear in this
appendix. Further information on these diseases can be found in the embedded
documents in section 8.1.
See reference section (page 17-18) for full details.
Table 1 – Clinical features of gastrointestinal infections, infestations and intoxications
Causative agent
Aeromonas sp
Bacillus cereus
emetic syndrome
diarrhoeal
syndrome
Bacillus subtilis
group
B. subtilis
B. licheniformis
Campylobacter sp
Cholera
Clostridium
botulinum
Clostridium
perfringens
Cryptosporidium
sp
Dysentery amoebic
Escherichia coli
(ETEC) (EPEC)
Incubation period
Common clinical features
Vomiting, diarrhoea
Mode of transmission
Water and contaminated
food
1 to 6 hours
Nausea, vomiting & abdo
pain
Diarrhoea, abdominal pain
Ingestion of contaminated
food
10 minutes to 14
hours
2 to 14 hours
1 to 10
days(usually 2 to 5
days)
a few hours to 5
days (usually 2 to
3 days)
2 hours to 8 days,
(commonly 12 to
36 hrs)
4 to 24 hours
(usually 12 to 18
hours)
1 to 14 days
Nausea, vomiting,
diarrhoea
Diarrhoea, abdominal pain
Abdominal pain, profuse
diarrhoea malaise; vomiting
is uncommon
Profuse watery diarrhoea
rapid dehydration
Ingestion of contaminated
food
Dysphonia, diplopia,
dysphagia ptosis
Ingestion of contaminated
food
Diarrhoea and abdominal
pain
Ingestion of contaminated
food
Watery or mucoid diarrhoea
Usually 2 to 4
weeks
10 to 72 hours
9 t0 12 hours
Bloody diarrhoea
Faecal oral, contaminated
water, animal contact
Faecal oral
6 to 24 hours
Diarrhoea
Ingestion or handling of
contaminated food or
water
Contaminated food or
water
Faecal oral, occasionally
food or water
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Causative agent
Incubation
period
Common clinical
features
Mode of transmission
Escherichia coli
(VTEC)
1 to 8 days
Ingestion of contaminated
food, faecal oral
Giardia
3 to 25 days
Haemorrhagic colitis
haemolytic uraemic
syndrome
Diarrhoea, abdominal
cramps
Hepatitis A virus
15 to 50 days
Fever, malaise, nausea,
jaundice
Listeriosis
1 day to >3 months
Septicaemia, meningitis,
influenza like illness
Salmonella Typhi
Paratyphi
1 to 3 weeks
1 to 10 days
Salmonellas (nonenteric fever)
12 to 72 hours
(usually 12 – 36
hours)
12hrs to 7 days
Fever, malaise, nausea,
constipation (early),
diarrhoea (late)
Diarrhoea, vomiting, and
fever
Shigella sp
Staphylococcus
aureus
Vibrios (noncholera)
eg V.
parahaemolyticus
Viral
gastroenteritis
 Norovirus

Rotavirus
Worms
Yersinia sp
1 to 7 hours
(usually 2 to 4
hours)
2 to 48 hours
(usually 12 to 18
hours)
usually 10 to 50
hours
Ingestion of contaminated
food or water
S. sonnei – generally mild
Bloody diarrhoea Other
species more severe
Vomiting, abdominal pain
Faecal oral, occasionally
contaminated food or
water
Ingestion of contaminated
food
Diarrhoea, fever
Ingestion of contaminated
food particularly shellfish
Vomiting predominates,
diarrhoea, fever
Diarrhoea, vomiting
From cases (including 48
hrs post recovery)
Faecally-orally by
ingestion inhalation of
vomit and fomites
Wide range (see text)
Faecal oral
Watery diarrhoea,
abdominal pain fever,
arthritis
Ingestion of contaminated
food
24-72 hrs
Life cycle
dependant
3 to 7 days
Faecal oral; ingestion of
contaminated food or
water
Faecal oral; ingestion of
contaminated food or
water
Contaminated food or
vertical transmission or
rarely HCAI
Ingestion of contaminated
food or water
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Acute Encephalitis
Control of human source
Statutorily notifiable
Cases
Dependent on cause. Expert
infectious disease advice may be
needed.
Contacts/exposed
Unlikely that contacts will require
any intervention unless a
particular virus can be transmitted
from person to person.
Isolation/exclusion
Dependent on cause
Cause
There are many types of encephalitis, most of which are
caused by viral infection.
Reservoir
Human and a wide variety of animals can carry viruses
associated with encephalitis. Many are outside the UK.
Transmission.
Various vectors including mosquitoes, ticks, and a wide
variety of animals.
Other relevant features
Usually notified as part of viral meningitis. May be
associated with long-term neurological diseases. Just
after the first World War, a viral disease, encephalitis
lethargica, attacked almost 5 million people throughout
the world, and then suddenly disappeared in the 1920s.
Known as sleeping sickness in the United States, this
disease killed one third of its victims and in many
others led to post-encephalitic parkinsonism
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Acute Poliomyelitis
Control of human source
Statutorily notifiable
Cause
Poliovirus
Cases
Isolation and enteric precautions
Reservoir
Humans
Contacts/exposed
Immunisation
Transmission.
Person to person faecal-oral route
Isolation/exclusion
Isolation of contacts required
Other relevant features
Although no cases in UK in recent years still endemic
in many countries of the world. An acute case in this
country would trigger a major incident.
Aeromonas
Control of human source
Statutorily notifiable if thought to be
the cause of food poisoning. Person
to person spread is rare.
Cases
Enteric precautions.
Contacts
Clinical surveillance only.
Exclusions
Cases in risk groups A to D for 48
hours after first normal stool.
Microbiological clearance
None required
Cause
Aeromonas hydrophila, A. sobria or other members
of the group.
Reservoir
Common free-living organisms in aquatic
environments.
Transmission
Consumption of untreated water, contaminated
shellfish, and foods eaten raw or washed in untreated
water.
Other relevant features
Pathogenicity of many strains is unproven. Some
strains produce a toxin like that of Vibrio cholerae.
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Amoebic Dysentery
Control of human source
Dysentery is statutorily notifiable.
Cause
Entamoeba histolytica.
Cases
Enteric precautions until treatment
is completed.
Reservoir
Human gastrointestinal tract.
Contacts
Screen household contacts.
Microbiologically to detect cyst
excreters.
Exclusions
48 hours after first normal stool. C
and D require microbiological
clearance.
Transmission
Waterborne or via contaminated raw or undercooked
foods. Transmission is usually through faecal oral
spread from a chronically ill or asymptomatic cyst
shedder.
Other relevant features
Cysts resist standard chlorination but are destroyed
by hyperchlorination or iodination.
Microbiological clearance
Cases in risk groups C and D: One
stool, obtained at least one week after
the END of treatment, should be
examined for E. histolytica cysts.
Careful assessment of excreters is
needed to evaluate significance
because pathogenic E. histolytica
cysts are morphologically
indistinguishable from those of the
non-pathogenic E.dispar. Referral of
specimens for cyst typing can be
undertaken.
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Anthrax
Control of human source
Statutorily notifiable. A possible
association with bioterrorism (CBRN).
Cause
Anthrax is a bacterial infection caused by Bacillus
anthracis.
Cases
Cases do not require isolation after
they have been decontaminated.
Reservoir
The spores produced by the bacterium may survive
for periods up to 30 years or longer and are
resistant to desiccation.
Contacts/exposed
Contacts of anthrax spores as a result
of CBRN need decontamination.
Antibiotic prophylaxis and
immunization may be needed.
Isolation/exclusion
Contacts should be isolated until
decontaminated. If Anthrax is
considered as part of CBRN major
incident plans should be activated.
Transmission.
Anthrax is primarily a disease of animals not
humans. It is extremely unusual for anthrax to be
transmitted from person to person. Transmission is
by contact with infected animals, contaminated
hides, wool or products made from these or contact
with soil associated with infected animals or
contaminated bone meal or through deliberate
release as in bioterrorism.
Other relevant features
Incubation period is 1 - 7 days, although can be up
to 60 days.
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Bacillus species food poisoning
Control of human source
Statutorily notifiable as food
poisoning. Person-to-person spread
does not occur.
Cause
1. Bacillus cereus.
2. Bacillus subtilis group, including B.
licheniformis.
Cases
Enteric precautions.
Reservoir
No human or animal sources. Environment,
soil, sediments, dust, vegetation. Food: cereal
products herbs and spices, dried foods, milk and
dairy products, meat and meat products.
Contacts
No action necessary.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Transmission
Contaminated cooked foods subjected to
inadequate post-cooking temperature control
during cooling and storage.
B.cereus: mainly rice dishes; occasionally pasta,
meat or vegetable dishes, dairy products, soups,
sauces, sweet pastries.
B.subtilis group: mainly meat or vegetable with
pastry products, cooked meat or poultry
products, occasionally bakery products,
including bread, crumpets, sandwiches, and
ethnic meat or seafood dishes.
Other relevant features
B.cereus causes two distinct clinical
presentations – the emetic and diarrhoeal
syndromes – that are associated with different
toxins.
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Campylobacter
Control of human source
Statutorily notifiable as food poisoning if
thought to be foodborne or waterborne.
Cases
Enteric precautions.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Predominantly Campylobacter jejuni.
C. coli and other Campylobacter species (eg C.
lari and C. fetus) are much less frequently
implicated. C. jejuni predominantly causes
enteric illness (acute gastroenteritis,
colitis),while C. fetus is the major pathogen in
extraintestinal illness (systemic illness with
bacteraemia, meningitis, vascular infection,
abscesses, occasionally gastroenteritis).
Reservoir
Campylobacter infection is a zoonosis. The
reservoir for C. jejuni is very varied and
includes the gastrointestinal tract of birds
(particularly poultry) and mammals (i.e. cattle
and domestic pets). C.coli is most commonly
isolated from pigs, and C. fetus from cattle and
sheep.
Transmission
Transmission is predominantly via contaminated
food or water. Person-to-person transmission
can occur if hygiene is poor
Other relevant features
Not all Campylobacter infections result in
illness. The infective dose is considered to be
low. Person-to-person transmission can occur
and school age children can rarely transmit
campylobacter infection. Occupational exposure
has been implicated in some illness.
Campylobacter is a fairly frequent cause of
travellers’ diarrhoea. Campylobacter does not
multiply on food and foodborne disease
outbreaks are rarely recognised. In a recent
review of outbreaks the most frequently
identified food-handling fault was crosscontamination. Transmission from ill food
handlers is extremely rare.
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Cholera
Control of human source
Statutorily notifiable.
Cases
Enteric precautions. Cases should
normally be admitted to an Infectious
Diseases Unit.
Contacts
Clinical surveillance of people who
shared food and drink with case for 5
days from shared exposure. If
secondary transmission is likely,
chemoprophylaxis with tetracycline,
doxycycline or erythromycin.
Exclusions
48 hours after first normal stool.
Microbiological clearance
Where indicated, two consecutive
negative stools taken at intervals of at
least 24 hours apart.
Cause
Vibrio cholerae O1 (biotypes classical and El Tor)
and V. cholerae O139. Clinical disease is
mediated by the production of an enterotoxin.
Reservoir
The natural reservoir is aquatic environments.
Vibrio cholerae lives attached to a special sort of
algae or to crustacean shells and zooplankton. In
favourable environmental conditions V. cholerae
survives for years in a free-living cycle without
human intervention. When growth and survival
conditions are sub-optimal, V. cholerae switches
to a viable, non-culturable state. Although humans
infected with V. cholerae may shed organisms
for prolonged periods, their importance as a
reservoir is trivial compared with the aquatic
environment.
Transmission
Transmission is predominantly through
consumption of polluted untreated water,
contaminated shellfish and raw food or food
washed in contaminated waters. V. cholerae has
been shown to survive for up to 14 days in some
foods, particularly when the food was
contaminated post preparation. Symptomatic and
asymptomatic food handlers have been implicated
in foodborne outbreaks. Although there are reports
of person-to-person transmission in the literature, it
has been suggested that other potential risk factors
might have been overlooked in disease
transmission in some of these outbreaks.
Other relevant features
Cholera is rare in the United Kingdom (UK) and
only occurs in imported cases. For person-toperson transmission to occur a large inoculum is
required. Vaccination plays no part in the
management of contacts or the control of
outbreaks.
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Clostridium botulinum – botulism
Control of human source
Statutorily notifiable as food poisoning.
Cause
Clostridium botulinum neurotoxin.
Person-to-person spread does not occur.
Reservoir
Soil and aquatic sediments.
Cases
Hospital admission imperative. Immediate
investigation with associated laboratory
studies to identify the source. No other
control measures are required for the case.
Others exposed to the same source
Immediate identification and treatment of
others at risk is mandatory. Examination of
faecal and serum specimens of people
exposed may be indicated.
Contacts
Only important as potential cases if they
have been exposed to the same risk of
infection.
Exclusions
None.
Microbiological clearance
None required.
Transmission
Foodborne botulism in adults is generally
caused by ingestion of food contaminated
with toxin. Under processed non-acid foods
or foods contaminated after canning or
bottling (eg canned fish) may provide
anaerobic conditions and suitable pH for the
organism to multiply during prolonged
storage at room temperature. Infant botulism
is caused by ingestion of spores. Wound
botulism can also occur when spores get into
the body via a contaminated wound.
Other relevant features
Foodborne botulism is rare in the UK, but it
is a severe disease with a high mortality rate.
A single case, especially if caused by eating
a commercially produced food, may signal a
national emergency and prompt action is
essential at any time of the day or night. The
local microbiologist and CCDC should be
contacted urgently, as should HPA Centre
for Infections (telephone 020 8200 4400) or
HPS (0141 300 1100). Suspect foods and
clinical specimens (serum, vomit, faeces)
(including from Scotland) should be sent
immediately by courier to the HPA Centre
for Infections, (telephone 020 8200 4400) for
testing. Botulism is ultimately a clinical
diagnosis that laboratory tests can confirm
but not refute. Once a clinical diagnosis is
made botulinum antitoxin must be given as
soon as possible. Details of holding centres
nationwide are available from the HPA duty
doctor. Enforcement officers should refer to
the Food Safety Act 1990 – Code of Practice
No. 16: enforcement of the Food Safety Act
1990 in relation to the food hazard warning
system.
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Clostridium difficile antibiotic-associated diarrhoea (AAD)
Control of human source
Cases
Enteric precautions. Stop predisposing
antibiotic therapy. Initiate appropriate
treatment.
Contacts
Monitor susceptible individuals
(elderly, all those receiving antibiotics)
for diarrhoeal illness.
Exclusions
48 hours after first normal stool.
Asymptomatic carriers should not be
excluded from nursing homes/
hospitals.
Microbiological clearance.
None required.
Cause
Clostridium difficile, which produces toxins
damaging to the colonic mucosa.
Reservoir
Human gastrointestinal tract. Spores survive in the
environment around symptomatic cases.
Transmission
Person-to-person by the faecal-oral route and by
environmental contamination. Antibiotic use
(especially broad-spectrum agents) disrupts the
normal bacterial flora and induces susceptibility to
C. difficile colonisation and overgrowth.
Other relevant factors
AAD ranges in severity from mild diarrhoea to
severe pseudomembranous colitis. Outbreaks
occur in hospitals and nursing homes. The elderly
are particularly susceptible. Young children (aged
less than 2 years) can carry C. difficile as part of
the normal bowel flora and asymptomatic carriage
occurs in a small proportion of adults.
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Clostridium perfringens food poisoning
Control of human source
Statutorily notifiable as food poisoning.
Person-to-person spread does not occur.
Cases
Enteric precautions.
Contacts
No action necessary.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Clostridium perfringens enterotoxin.
Reservoir
Gastrointestinal tract of food animals, soil and
dust.
Transmission
Contaminated cooked meat and poultry dishes
subjected to inadequate temperature control after
cooking or cooling, inadequate reheating before
consumption.
Other relevant features
C. perfringens enterotoxin is produced in the
intestine after ingestion of large numbers
(Usually >105) of organisms. The toxin is
produced when the ingested organisms transform
into spores in the intestine.
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Cryptosporidiosis
Control of human source
Statutorily notifiable as food poisoning
if thought to be food or waterborne.
Cases
Enteric precautions.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool. Cases
should also avoid using swimming
pools for two weeks after the first
normal stool.
Microbiological clearance
None required.
Cause
Cryptosporidium spp.
Reservoir
Gastrointestinal tracts of humans and animals.
Transmission
Direct or indirect contact with infected animals.
Person-to-person spread, particularly in
households, healthcare and nurseries. Water
contaminated directly or indirectly with faeces.
Outbreaks have been associated with public and
private water supplies, swimming pools and, more
rarely, contaminated food. Seasonal outbreaks are
associated with farm visits to feed and handle
lambs and calves.
Other relevant features
Oocysts resist standard chlorination.
Large numbers of organisms are excreted during
acute infection. The infectious dose is low. Since
oocysts can continue to be shed following
cessation of diarrhoea, it is
recommended that cases avoid using swimming
pools for normal stool. Immunocompromised
individuals are particularly susceptible and may be
unable to clear the parasite. Anyone whose T cell
function is compromised should be advised to boil
and cool their drinking water, and water for
making ice, from whatever source.
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Cyclosporiasis
Control of human source
Statutorily notifiable as food poisoning.
Direct person-to-person transmission is
unlikely.
Cases
Enteric precautions. Treatment with
trimethoprim sulphamethoxazole is
rapidly effective.
Contacts
No action necessary.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Cyclospora cayetanensis.
Reservoir
Human gastrointestinal tract.
Transmission
Routes of transmission are poorly understood.
Outbreaks have been associated with the
consumption of soft fruit and vegetables (foods
that are difficult to wash and are eaten raw) and
drinking water.
Other relevant features
Direct person-to-person transmission is unlikely
since oocysts require a maturation period after
shedding and are only infectious once spores are
produced. Food handlers could contaminate food
for later consumption. Diarrhoea may follow a
relapsing and remitting course.
Immunocompromised people may be infected for
some months but treatment will clear the
infection.
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Diphtheria
Control of human source
Statutorily notifiable. Diptheria is a
public health emergency. The first action
is to determine whether it is a toxigenic
diphtheria (if it is not then no public
health action is required).
Cause
Toxin carried by some Corynebacterium
diphtheriae and some Corynebacterium ulcerans
Cases
Isolate in hospital
Transmission.
Contact with a patient or carrier; more rarely,
contact with articles soiled with discharges from
lesions of infected people.
Contacts/exposed
Contacts should receive antibiotics. All
contacts should be monitored daily for 7
days to ensure they are well.
Immunization boosters as recommended.
Isolation/exclusion
Adult contacts that are food handlers
should be excluded from work until
found to be culture negative (diphtheria
is occasionally transmitted by food and
milk).
Reservoir
Humans
Other relevant features
Classical respiratory diphtheria is characterised
by the insidious onset of membranous
pharyngitis with fever appearance. Cutaneous
diphtheria usually appears on exposed body
parts, especially the legs. The lesions start as
vesicles and quickly form small, clearly
demarcated, and sometimes multiple ulcers.
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Escherichia coli – Vero cytotoxin-producing (VTEC)
Control of human source
Statutorily notifiable if thought to be
food poisoning. The informal reporting
of haemolytic uraemic syndrome (HUS),
particularly with a diarrhoeal prodrome,
is to be encouraged.
Cases
Enteric precautions. Hospital admission
if haemorrhagic complications occur.
Isolation only during acute diarrhoeal
phase.
Contacts
Contacts in risk groups A to D should be
screened microbiologically, initially to
identify excreters and subsequently for
microbiological clearance (below).
Authorities must satisfy themselves of
the adequacy of hygiene and toilet
facility arrangements. Hand washing by
children must be supervised in nurseries
and infant schools.
Exclusions
48 hours after the first normal stool for
cases not in risk groups.
Cases and contacts in risk groups A to D
until microbiological clearance is
obtained.
Microbiological clearance
Risk groups A to D only – two negative
faecal specimens taken at intervals of not
less than 24 hours. The ease of spread
means that it may be wise to ensure that
all cases and contacts in high-risk groups
in a given household or similar setting
are no longer excreting before being
allowed to return to work, school, etc.
Such risks depend in part on the risk of
transmission in the household and can
ultimately only be assessed locally.
Cause
Vero cytotoxin-producing Escherichia coli. The
commonest serotype in the United Kingdom is
E.coli O157:H7.
Reservoir
The gastrointestinal tract of cattle, sheep, goats
and other, particularly domesticated, animals.
The disease is a zoonosis.
Transmission
Person-to-person spread can occur by direct
contact (faecal-oral), particularly in households,
nurseries and infant schools. (In confirmed
cases of VTEC infection, younger primary
school children, whose ability to practice
personal hygiene may be limited, should be
managed as risk group B). Evidence for spread
from asymptomatic healthcare staff and food
handlers remains elusive. Primary infections are
acquired by: contact with infected animals or
their faeces, particularly on farms, including
‘open’ farms. Contaminated foodstuffs – beef
and other meat products (for example,
undercooked beef burgers and contaminated
cooked meats) and raw dairy products have been
associated with cases or outbreaks. Extensive
waterborne outbreaks have occurred.
Other relevant features
VTEC may give rise to a haemorrhagic colitis
and about 5% of cases progress to the
haemolytic uraemic syndrome, of which the case
fatality rate is about 2%. Antibiotic treatment
may be harmful. Diagnosis may be made by a
serum sample even after microbiological
clearance and a salivary sample may be a
possible alternative, particularly for younger
children.
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Escherichia coli other than VTEC
Control of human source
Cases
Enteric precautions for EPEC, EAggEC
and ETEC. Cases of EPEC admitted to
hospital should be isolated if possible.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Some classical enteropathogenic E.coli (EPEC)
belonging to a small number of serotypes cause
sporadic cases and outbreaks of diarrhoea in
children, usually under the age of 2 years. A
wider range of EPEC strains have caused
sporadic cases and outbreaks affecting adults.
Enterotoxigenic E.coli (ETEC) are a major cause
of travellers’ diarrhoea.
Enteroaggregative E.coli (EAggEC) cause
sporadic cases and outbreaks affecting all ages.
Associated with travel abroad. Other types such
as enteroinvasive E.coli (EIEC) rarely occur in
the UK.
Reservoir
Human gastrointestinal tract, including ‘classical’
EPEC. Infection with some EPEC strains may be
zoonotic.
Transmission
EPEC in day care units and nurseries transmitted
from person-to-person by the faecal oral route.
Sporadic cases and outbreaks of non-classical
EPEC infection may be caused by contaminated
food. ETEC in contaminated food and water.
Person-to-person spread is unusual. EAggEC in
contaminated food.
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Food Poisoning
Control of human source
Statutorily notifiable
Cases
Investigation if possible. Promotion of
good hygiene.
Cause
Food poisoning may be notified without
information on a causative agent. It may be
caused by any of the agents within this disease
list.
Contacts
Clinical surveillance only
Exclusions
Cases in risk groups A to D for 48 hours
after first normal stool.
Microbiological clearance
Not possible if food poisoning with no
identifiable cause.
Giardiasis
Control of human source
Statutorily notifiable as food poisoning
when believed to be foodborne.
Antimicrobial treatment of individual
cases forms the basis of control.
Cases
Enteric precautions.
Contacts
Screening household contacts may
identify excreters who need treatment.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Giardia duodenalis (syn. Giardia lamblia, syn.
Giardia intestinalis).
Reservoir
Human gastrointestinal tracts. Animal hosts
have been described but this is seldom the source
of disease in humans.
Transmission
Person-to-person. Faecal-oral route is important
in young children. Spread within families is
common. Foodborne outbreaks have occurred,
particularly linked to infected food handlers or
contacts. Water contaminated with faeces.
Outbreaks have been associated with drinking
and recreational waters.
Other relevant features
Cysts resist the levels of chlorine normally used
in drinking water treatment.
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Hepatitis A
Control of human source
Statutorily notifiable as viral hepatitis.
Cause
Hepatitis A virus (HAV).
Cases
Enteric precautions.
Reservoir
Human gastrointestinal tract.
Contacts
Vaccination of household contacts should
be considered if the index case was
identified within one week of onset of
illness (usually defined by jaundice) or if
at continuing risk. Alternatively, passive
immunisation with human normal
immune globulin to family, sexual,
household, and other close contacts
should be considered. Hand washing by
children must be supervised in nurseries
and infant schools. Authorities must
satisfy themselves that hygiene and toilet
facilities are adequate. Consider active
immunisation in selected outbreaks and
seek advice.
Transmission
Person-to-person spread is common by faecaloral route, including through sexual intercourse
and probably through urine. Food contaminated
by an infected person. Consumption of
contaminated untreated water, contaminated
shellfish, and foods eaten raw or washed in
these waters. Other vehicles have been fresh
picked fruits and products such as ice cream
made from them.
Other relevant features
Young children are commonly asymptomatic.
Older children and adults usually have
symptoms. The period of infectivity starts 10 to
14 days after exposure and a similar interval
before the onset of jaundice but is maximal just
before jaundice develops. Specific HAV IgM is
Others exposed
People who have recently been exposed to diagnostic but not detected until 5 days after
food prepared by a case may benefit from onset of symptoms. Susceptibility may be
active or passive immunisation.
determined by the examination of a blood or
saliva specimen for anti-HAV IgG.
Bloodborne transmission is described but rare,
Exclusions
All cases including those in risk groups A associated with injecting drug use or blood
to D should be excluded for 7 days after
products.
onset of jaundice and/ or other symptoms.
Microbiological clearance
None required.
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Hepatitis E
Control of human source
Statutorily notifiable as viral hepatitis.
Cause
Hepatitis E Virus
Cases
Enteric precautions
Reservoir
Gastrointestinal tract (human and animals)
Contacts
Although Hepatitis E infection usually
produces only mild disease. However,
when hepatitis occurs in pregnant women,
there may be a case fatality of up to 20%
in the third trimester.
Transmission
Especially water contaminated by an infected
person/animal.
Food borne infection also occurs.
Secondary transmission low (1-2%).
Exclusions
For all cases and those in Risk Groups up
to 14 days after first experiencing
symptoms.
Advise to avoid contact with pregnant
women.
Other relevant features
Hepatitis E has historically been seen as a
disease associated with travel to countries
where it occurs more commonly in the
population, including the Indian subcontinent,
Africa and central America.
Most clinically reported cases occur in young or
middle aged adults.
Microbiological clearance
None required
Legionnaire’s disease
Control of human source
Legionnaire’s disease is a notifiable
disease.
Cases
Isolation not required
Contacts / exposed
Administer Legionnaire’s disease
questionnaire.
Cause
Bacteria - Legionella pneumophila
Reservoir
Ubiquitous – widely distributed in soil and water.
Particularly in water-cooled air conditioning systems
and cooling towers.
Transmission
Mode of transmission – waterborne, thought to be
mainly aerosol. Not person to person.
Isolation / exclusion
Not required
Other relevant features
Patients are often severely ill. Pontiac fever is a milder
form of the disease without pneumonia. Incubation
period is 5-66 hours for Pontiac fever and 2-10 days for
Legionnaire’s disease.
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Leprosy
Control of human source
It is a statutorily notifiable disease
Cause
Mycobacterium leprae
Cases
None except lepromatous leprosy. None
for chronic cases.
Reservoir
Humans
Contacts / exposed
Clinical surveillance
Transmission.
Close personal contact
Other relevant features
Isolation / exclusion
Assistance of DPH and/or EH may be
requested in locating family and
household contacts for examination.
Contracted outside UK
The HPU team receives an annual
request for information about known
cases of leprosy.
Leptospirosis
Control of human source
Statutorily notifiable as a causative agent.
Cases
Isolation not required
Contacts / exposed
No action required
Environmental control
Ensure contamination of domestic
environment by urine of potentially
infected animals is avoided.
Ensure rodent control adequate. If
rodents a particular problem consider
ways to reduce their population and make
the environment unsuitable for them.
Eliminate potential contamination or
prohibit use of water
Isolation / exclusion
Not required
Cause
Spirochaete
Leptospira hardjo (cattle) & Leptospira
icterohaemorrhagiae (rats)
Reservoir
Wild and domestic animals, rats, pigs, cattle, dogs,
badgers. Spirochaetes may be present in the urine after
recovery.
Transmission.
Through direct or indirect (the majority) contact with
infected animal urine, or, less frequently, from animal
bites, handling infected animal tissues or swallowing
contaminated food or water. Person to person spread is
exceptionally rare. The bacteria enter through skin
abrasions or through the eyes nose and mouth.
Other relevant features
Weil’s disease – may lead to renal failure.
Vaccine is only licensed for veterinary use.
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Listeriosis
Control of human source
Treatment of individual cases and
removal of contaminated foods.
Statutorily notifiable as food poisoning.
Person to person spread does not occur
except during the neonatal period.
Cases
Admission to hospital and treatment with
antimicrobial agents
Cause
Listeria monocytogenes
Reservoir
Environment: soil, water, drains, food production areas.
Consumption of heavily contaminated ready-to-eat food
products, usually with a high degree of processing, of
neutral pH, and with an extended refrigerated shelf life.
Gastrointestinal tract of animals and birds.
Transmission.
Foods associated with transmission have involved dairy
products, meat-based products, seafood and vegetableIsolation
Hospitalised pregnant women or neonates based products.
of positive women should be isolated –
inform ICT.
Other relevant features
Contacts / exposed
Clinical surveillance only
Exclusion
Most cases present as septicaemia and/or meningitis in the
immunocompromised, or as an infection of pregnant women
and fetus/neonate. Pregnant women present with a series of
pyrexial influenza-like illnesses. Some stains of
L.monocytogenes also cause a diarrhoeal illness plus fever.
Not required
Malaria
Control of human source
Statutorily notifiable.
Cause
A parasitic disease caused by Plasmodium species.
Cases
Isolation not required.
Reservoir
Humans
Contacts / exposed
There are no public health actions, as the
disease does not spread here.
However, a comprehensive questionnaire
is usually sent to the patients who have
been notified
Transmission.
Anopheles Mosquito bites
Other relevant features
Imported disease only (at present)
Isolation / exclusion
Not required
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Marine biotoxins – marine algal shellfish poisoning syndromes and ciguatera poisoning
Control of human source
Statutorily notifiable as food poisoning.
Person-to-person spread does not occur.
Cases
Enteric precautions only.
Cause
Ingestion of toxic algae and retention of the
toxins by filter-feeding bivalves and some fish.
Concentration of toxins up the food chain by
some carnivorous gastropods, crustaceans, and
fish.
Contacts
Clinical surveillance only.
Reservoir
Toxic seafood.
Exclusions
None required.
Transmission
Consumption of toxic seafood.
Microbiological clearance
None required.
Other relevant features
The main syndromes are amnesic shellfish
poisoning, diarrhetic shellfish poisoning,
neurotoxic shellfish poisoning (NSP), paralytic
shellfish poisoning (PSP) and ciguatera
poisoning. A wide range of gastrointestinal and
neurological symptoms is often manifest, for
example, respiratory paralysis in PSP, a reversal
of hot-cold temperature sensation in NSP and
ciguatera poisoning. Symptoms are dose related
and mild cases of all these syndromes may only
suffer gastrointestinal effects. All the toxins are
heat stable and not removed by cooking and
processing. There are no known antidotes.
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Marine biotoxins – scombrotoxic poisoning
Control of human source
Statutorily notifiable as food poisoning.
Person-to-person spread does not occur.
Cases
None required.
Contacts
Clinical surveillance only.
Exclusions
None required.
Microbiological clearance
None required.
Cause
Conversion of histidine to histamine by growth
of some bacteria. Histidine is naturally present
at high levels in the flesh of some fish such as
tuna, mackerel and sardines.
Reservoir
Natural flora of fish and environmental
contamination.
Transmission
Inadequate temperature control of fish at any
stage after catching. Histamine is heat stable
and not reduced by cooking or processing.
Other relevant features
The symptoms of some patients are sufficiently
severe that they visit accident and emergency
departments.
Measles
Control of human source
Statutorily notifiable.
Cause
Virus (Morbillivirus)
Cases
Measles is most infectious from 4 days
before the appearance of the rash until
4 days afterwards
Reservoir
Humans
Transmission.
Respiratory droplets, (airborne)
Contacts / exposed
For measles, vaccination of susceptible
siblings and other close contacts is
effective up to 72 hours after contact.
HIG may be considered for those
babies between 6-8 months or pregnant
women with no infection or
immunisation history.
Other relevant features
SSPE (subacute sclerosing pan-encephalomyelitis) is
the most severe complication of measles. It is rare
occurring in less than 1 in 100,000 cases of measles.
Isolation / exclusion
School children and others 4 days from
onset of rash
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Meningitis (including septicaemia)
Control of human source
Statutorily notifiable. This disease is
notifiable whether caused by
Meningococci or other bacteria
(Pneumococci, Listeria) or viruses.
Meningococcal septicaemia is notified
separately from meningococcal
meningitis.
Cases
Isolated in hospital until treated.
Cause
Meningococcal bacteria (Neisseria meningitidis) and other
bacteria, viruses, and other organisms,
Reservoir
Humans
Transmission.
Person to person droplet spread
Other relevant features
A major cause of public health concern.
Contacts / exposed
Prophylaxis antibiotics are
administered following advice from
HPU team. Immunisation may be
required depending on type.
Isolation / exclusion
Siblings and other contacts do NOT
need to be excluded from normal
activities including school.
Mumps
Control of human source
Statutorily notifiable.
Cause
Mumps virus (Paramyxovirus)
Cases
Suggest avoid close contact with
susceptible persons.
Salivary swabs plus letter should be
sent to the GP who should return swab
taken to CfI. Immune status of patient
should be ascertained.
Reservoir
Humans
Contacts / exposed
Immunise contacts with MMR.
Note that vaccinations must not be
given in pregnancy. Swabs are needed
for enhanced surveillance, as many
notifications on clinical grounds are
erroneous.
Transmission.
Airborne, droplet, direct contact with saliva. Only
moderately transmissible.
Other relevant features
Preventable through MMR immunisation. Mumps
meningitis and encephalitis although usually mild are
common features.
Isolation / exclusion
School children 5 days from onset of
swelling
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Non-cholera vibrios
Control of human source
Statutorily notifiable as food poisoning.
Cases
None required.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Halophilic vibrios (Vibrio parahaemolyticus, V.
vulnificus, V. fluvialis, V. hollisae); nonhalophilic vibrios (non-O1 and non-O139 Vibrio
cholerae, V. mimicus). V. vulnificus is the most
virulent of the non-cholera vibrios and is
primarily associated with severe, soft tissue
infections or septicaemia, or both, rather than
diarrhoea.
Reservoir
These organisms are part of normal marine flora
and proliferate during the summer months.
Transmission
Transmission of halophilic vibrios is foodborne
via consumption of raw or undercooked
contaminated shellfish Transmission of nonhalophilic vibrios is via consumption of very
large inocula from contaminated water and,
occasionally, food. Person-to-person
transmission
has not been demonstrated. Secondary spread is
rare, even where sanitation is sub-optimal,
suggesting that the infective dose for normal,
healthy individuals is relatively high.
Other relevant features
Non-cholera Vibrio infections in the UK tend to
be imported in travellers returning from warmer
climates. Non-O1 V. cholerae does not seem to
cause sweeping epidemics, unlike V.cholerae O1
and V. cholerae O139, but explosive outbreaks
have been caused by a few non-O1 strains.
Genetic differences mediate these differences in
epidemiological behaviour.
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Noroviruses (Norwalk-like viruses [NLV], small round structured viruses [SRSV])
Cause
Norovirus genogroup 1 or 2.
Control of human source
Statutorily notifiable if thought to
be food poisoning.
Reservoir
Human gastrointestinal tract.
Cases
Enteric precautions with particular
attention to environmental contamination,
relating to vomit, especially of toilets and
wash hand basins, as well as soft
furnishings. Cases occurring in
institutions should be isolated where
practicable.
Contacts
Clinical surveillance. Do not transfer
patients during incubation period.
Authorities must satisfy themselves of the
adequacy of hygiene and toilet facilities
and arrangements.
Exclusions
48 hours after first normal stool.
Transmission
Person-to-person by the faecal-oral route; risk
of infection from aerosols or environmental
contamination due to projectile vomiting.
Water and foods contaminated by a
case/excreter. Particular problems arise with
ready-to-eat foods, which are extensively
handled, by a case or excreter during
preparation (e.g. salads & sandwiches).
Other relevant features
Infectivity lasts for 48 hours after resolution of
symptoms. Person-to-person spread is very
common and may be difficult to contain. Soft
furnishings may need to be steam cleaned.
Soiling with vomit should ideally be cleaned to
a radius of two metres and people taken out of
the area until it is done.
Microbiological clearance
None required.
Ophthalmia Neonatorum
Control of human source
Not statutorily notifiable according to
the new regulations.
Cases
Prevent contact with other neonates
until treated.
Contacts / exposed
Clinical surveillance
Cause
Neisseria gonorrhoea (an Sexually Transmitted) or
Chlamydia trachomatis or other bacteria such as
staphylococci
Reservoir - Human
Transmission.
Direct contact with infected birth passage. Secondary
spread by direct contact with eye discharge.
Other relevant features
Acute infection of the eye in first three weeks of life.
Gonorrhoea is now uncommon in pregnant women but
genital Chlamydia may be present in up to 5% of women.
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Plague
Control of human source
Statutorily notifiable. Maybe
considered a potential for CBRN.
Cause
Yersinia Pestis
Cases
Isolation required
Reservoir
Pathogen of Rodents
Contacts / exposed
Transmission.
By the bite of fleas infected with the organism.
Antibiotic prophylaxis for
household and close contacts.
Treat patient, clothing and
possessions with appropriate
insecticides. In the cae of urban
rats, houses, outhouses and
household furnishings should also
be disinfected.
Identify likely source of infection;
if abroad consider treating traveling
companions with insecticide. if in
the UK (unlikely) treat entire
house, furnishings and inhabitants
with insecticide and then act to
reduce rat population.
Other relevant features
Does not occur in the UK, but may be imported from
plague – infected areas in Africa, Asia and South America,
usually at times of epidemics. It is one of the diseases
covered by International Regulations.
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Rabies
Control of human source
Statutorily notifiable.
Cause
Rhabdovirus.
Cases
Person to person not documented but
theoretically possible. Therefore
isolate.
Reservoir
Wild and domestic animals
Transmission.
Bites, scratches and licks (present in saliva).
Contacts / exposed
Consider anti-rabies treatment in
contacts that have had an open
wound or mucous membrane
exposed to patient’s saliva.
Other relevant features
Several rabies-free countries including UK have
rabies-like virus in their bat populations. This includes
Australian Bat Lyssavirus in Australia, and European
Bat
Lyssavirus 1 and 2 in Europe and in the UK. The risk
from these viruses is likely to be low because the
incidence of acute infection and excretion of virus is
rare in bats and because humans are rarely exposed to
the most affected bat species (in the UK this is the
Daubenton’s bat). Specialist advice should be sought.
Relapsing fever
Control of human source
Not statutorily notifiable under the
new regulations.
Cause
Borrelia recurrententis – bacterium
Cases
Not after delousing.
Reservoir
Humans, rodents
Contacts / exposed
Delousing of clothes
Transmission.
Tickborne. Not person to person.
Isolation / exclusion
None required after delousing.
Other relevant features
Imported.
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Rubella
Control of human source
Statutorily notifiable.
Cause
Rubella virus (Togavirus)
Cases
Attempt to isolate from pregnant
women.
Reservoir
Humans
Contacts / exposed
Non-immune pregnant women should
consult GP/Obstetrician immediately.
Isolation / exclusion
Schoolchildren 6 days from onset of
rash
Transmission.
Person to person via respiratory droplets.
Other relevant features
A cause of severe congenital abnormality. Preventable
with MMR vaccine.
Rotavirus
Control of human source
Cases
Enteric precautions.
Contacts
Clinical surveillance only. Authorities
must satisfy themselves of the adequacy
of hygiene and toilet facilities and
arrangements.
Cause
Rotavirus groups A, B, and C (mainly group A
in the UK).
Reservoir
Human gastrointestinal tract.
Exclusions
48 hours after first normal stool.
Transmission
Person-to-person by faecal-oral route and by
environmental contamination. Children and the
elderly are at particular risk.
Microbiological clearance
None required.
Other relevant features
Person-to-person spread is very common.
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Salmonella (excluding typhoid and paratyphoid)
Control of human source
Statutorily notifiable as food
poisoning if thought to be
foodborne or waterborne.
Cases
Enteric precautions.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool.
Microbiological clearance
None required.
Cause
Salmonella spp. There are some 2,500 serotypes of
Salmonella, of which the two most commonly identified
in the UK, the rest of Europe and the United States, are
Salmonella enterica serovar Enteritidis and S.
Typhimurium.
Reservoir
Salmonellosis is a zoonosis. Salmonella spp. is found in
the gastrointestinal tract of a wide variety of wild and
domestic animals, birds, reptiles and amphibians. In
humans chronic carriage is rare, but organisms are
excreted by convalescent carriers, mild and unrecognised
cases. Children aged less than 5 years may shed
organisms for up to a year (median 10 weeks). Over the
age of 5 years the maximum duration of shedding
appears to be up to 12 weeks (median 4 weeks).
Transmission
Transmission is predominantly via contaminated food,
where very many food vehicles have been implicated,
although waterborne outbreaks have been documented.
Exotic Salmonella infections are documented following
exposure to exotic pets, especially reptiles (up to 90% of
reptiles are Salmonella carriers). Person-to-person
transmission is important, especially where cases have
diarrhoea. Infants and faecally incontinent adults pose a
greater risk of transmission than do asymptomatic
carriers. Hospital transmission from patients to staff has
been associated with handling of soiled linen, failing to
comply with barrier nursing and faecally incontinent
patients. On the other hand hospital transmission from
healthcare workers to patients appears to be low if
infection control measures are strictly adhered to. The
risk of transmission to neonates and infants from family
members, who are chronic carriers or who have been
recently infected, is high. Infected (but not necessarily
symptomatic) food handlers have been implicated in
outbreaks of salmonellosis.
Other relevant features
Although volunteer studies suggest that the infective
dose may be fairly high, data from outbreaks suggest that
low doses (<103) may produce illness and that the
ingested dose is an important determinant of incubation
period, symptoms, and disease severity.
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Scarlet fever
Control of human source
Statutorily notifiable
Cause
Streptococci (beta-haemolytic group A).
Cases
Strict isolation not required after starting
treatment
Reservoir
Man
Contacts
Clinical surveillance. Consider
prophylactic antibiotics in closed
communities. Swabbing may be
indicated.
Transmission
Direct contact and droplet spread
Other relevant features
Associated with long term heart valve damage.
Exclusion
Recommend 24 hour exclusion from
school if appropriate treatment has been
initiated.
Shigellosis (see additional policy)
Control of human source
Clinical dysentery is notifiable. Personto-person spread is common.
Cases
Enteric precautions.
Contacts
Contacts in risk groups A to D of cases of
S. dysenteriae, S. flexneri, S. boydii should
be screened microbiologically. Otherwise
clinical surveillance only. Authorities
must satisfy themselves of the adequacy
of hygiene and toilet facility
arrangements. Hand washing by children
must be supervised in nurseries and infant
schools.
Cause
Organisms of the genus Shigella that comprises
four species: S. sonnei, S. boydii, S. dysenteriae
and S. flexneri.
Reservoir
Human gastrointestinal tract.
Transmission
Faecal-oral from cases with diarrhoea,
particularly in households, children’s nurseries
and infant schools. Occasionally spread by
food and water, contaminated by cases.
Other relevant features
S. sonnei is endemic in the UK and usually only
causes a mild illness. S. boydii, S. dysenteriae
and most S. flexneri infections, originate outside
the UK and frequently present clinically as
Exclusions
S. sonnei: 48 hours after first normal stool. dysentery (diarrhoea with blood, mucous and
S. dysenteriae, S. flexneri, S. boydii
pus). S. dysenteriae 1 may be associated with
(microbiological clearance).
serious disease including toxic mega colon and
the haemolytic uraemic syndrome.
Microbiological clearance
Cases and contacts of S. dysenteriae, S.
flexneri, S. boydii in risk groups A to D –
two negative faecal specimens taken at
intervals of not less than 48 hours.
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Smallpox
Control of human source
Statutorily notifiable. Considered
potential problem for CBRN – public
health emergency
Cases
Strict isolation
Contacts / exposed
Isolation. Vaccine available.
Cause
Variola virus
Reservoir
Laboratories only
Transmission.
Person to person
Other relevant features
Global eradication certified 1979.
Isolation / exclusion
Isolation and discussion with outbreak
control / major incident team.
Staphylococcus aureus food poisoning
Control of human source
Statutorily notifiable as food poisoning.
Person-to-person spread does not occur.
Cases
Enteric precautions.
Contacts
Clinical surveillance.
Exclusions
48 hours after first normal stool. Risk
group C – exclude food handlers with
septic lesions on exposed skin from
work until successfully treated. Nasal
carriers do not usually need to be
excluded.
Microbiological clearance
None required after lesions are healed.
Cause:
Staphylococcus aureus enterotoxins.
Reservoir:
Infected exposed skin lesions, nostrils, or fingers
of food handlers. Rarely, infected animals.
Transmission
From skin flora or infections in food handlers of
cooked foods such as ham, meat, poultry, fish,
prawns, and cream cakes which are then stored at
room temperature for more than two hours and
eaten cold. Some outbreaks are associated with
canned foods contaminated after processing.
Since the toxins are heat stable, outbreaks have
been associated with heat-treated or dried foods.
Other relevant factors
Some 25% people may carry S. aureus in their
nose.
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Tetanus
Control of human source
Statutorily notifiable.
Cause
Toxin produced by Clostridium tetani bacterium.
Cases
No isolation
Reservoir
Intestines of horses and other animals
Contacts / exposed
No precautions required, but remind
about immunisation.
Transmission.
Tetanus spores enter through puncture wounds –
particularly road injuries.
Isolation / exclusion
None required.
Other relevant features
Preventable by immunisation.
Tuberculosis
Control of human source
Statutorily notifiable
Cause
Mycobacterium tuberculosis
Cases
Isolation during early treatment for
those with smear positive TB.
Otherwise most treated at home.
Reservoir
Humans primarily (other animal types)
Transmission
Inhalation of droplets.
Contacts/exposed
Contact tracing and treatment. This
process managed by the respiratory
department.
Isolation/Exclusion
Consideration of health care workers,
and those working in schools etc. Risk
assessment conducted by Respiratory
teams.
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Typhus fever
Control of human source
Statutorily notifiable.
Cause
Rickettsia prowazekii (obligate parasite bacterium)
Cases
Isolation not required.
Reservoir
Humans
Contacts / exposed
None required. Clinical surveillance
for similarly exposed. Insecticides in
endemic areas.
Transmission.
Body louse. Not person to person.
Other relevant features
A disease of tropical highlands
Isolation / exclusion
None required.
Viral Haemorrhagic fever
Control of human source
Statutorily notifiable. A public health
emergency
Cause
A variety of viruses (including Lassa, Ebola, Marburg,
Crimean-Congo)
Cases
Isolation in special isolation unit
Reservoir
Animal reservoirs
Contacts / exposed
Clinical surveillance
Transmission.
Bites, contact, person to person via blood and body fluids.
Isolation / exclusion
Asymptomatic contacts isolated at
home.
Other relevant features
Imported diseases requiring rapid communication between
departments.
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Whooping cough (pertussis)
Control of human source
Statutorily notifiable.
Cause
Bordatella pertussis
Cases
Suspected cases should be removed
from the presence of young children
and infants, especially non-immunised
infants, until the patients have received
at least 5 days of a minimum 14 day
course of antibiotics
Reservoir
Humans
Contacts / exposed
Non-immunised contacts may require
antibiotics and immunisation. Their
household contacts may also require
antibiotics.
Transmission.
Direct contact and respiratory secretions by airborne route.
Other relevant features
Parapertussis, caused by the bacterium B. parapertussis, is
similar to, although usually milder than pertussis
Isolation / exclusion
Exclude from nursery or school for
five days from starting treatment.
Worms (helminths)
Control of human source
Cases
Enteric precautions. Early treatment.
Cause, Reservoir, Transmission
Worms are classified into three groups: Nematodes
(roundworms), cestodes (tapeworms), and
trematodes (flukes).
Threadworm: keep fingernails short
and hands well washed. Regular
change of underwear, nightclothes and
bedclothes.
1. Nematodes (roundworms)
i) Threadworm (Enterobius vermicularis)
Eggs present in faeces and on perianal region.
Transmission – faecal-oral, on hands and under
nails as a result of scratching the itchy perianal
region. Clothing, particularly nightwear, and
Contacts
Threadworm: Treat all household
bedclothes may be contaminated.
contacts – screening not necessary.
ii) Whipworm (Trichuris trichiura)
Heavy infection may present as a diarrhoeal illness.
Strongyloides: Healthcare workers
Eggs must mature for 3 to 5 weeks in soil outside
should take particular care with the
the host before becoming infective.
stools, urine, and other body fluids of
iii) Roundworm (Ascaris lumbricoides)
patients with hyperinfestation as larvae Eggs must mature in the environment for 1 to 2
are infective via skin penetration.
weeks before they become infective. They may
remain alive outside the human host from months
Taenia solium: Screen serologically
to years.
household contacts of pork tapeworm
for evidence of cysticercosis.
iv) Hookworm (Necator americanus,
Continued……….. Ancylostoma duodenale)
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Exclusions
Threadworm: exclude cases in risk
groups A to D until treated.
Taenia solium: Exclude cases in risk
groups A to D until two negative
stools commencing 1 and 2 weeks post
treatment.
Microbiological clearance
Taenia solium: two negative stools at
1 and 2 weeks post treatment for cases
in groups A to D.
Infection of humans is via skin penetration by
larvae, as the eggs passed in faeces have to mature
in soil for seven to eight days to form infective
larvae.
v) Strongyloides stercoralis
Larvae passed in the stool are usually not infective
until they mature. However, patients with severe
immunodeficiency and the Strongyloides
hyperinfestation syndrome pass infective larvae in
stool and sometimes urine, which are infective to
humans by skin contact.
2. Cestodes (tapeworms)
i) Eggs of the fish tapeworm Diphyllobothrium
latum and the beef tapeworm
Taenia saginata are not infective to humans as the
lifecycle involves an intermediate host.
ii) Eggs of Taenia solium, the pork tapeworm
can produce cysticercosis in humans, a potentially
dangerous condition. NB The eggs of Taenia
solium and Taenia saginata are morphologically
identical. Speciation can be made only by
examining segments of the worm itself. Taenia
saginata is seen much more commonly than
Taenia solium in the UK.
iii) Eggs of the dwarf tapeworm Hymenolepis
nana are infective to humans.
3. Trematodes (flukes)
i) Trematode eggs are not directly infective to
humans as the lifecycle involves one or more
intermediate hosts.
Other relevant features
Apart from the threadworm Enterobius
vermicularis, intestinal helminth infections in the
UK are usually seen as imported cases
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Yellow fever
Control of human source
Statutorily notifiable.
Cause
Flavivirus
Cases
Universal precautions for blood and
body fluids.
Reservoir
Humans, monkeys.
Contacts / exposed
No action required unless exposure to
the vector (not in this country).
Transmission.
Mosquito bites (Aedes aegypti)
Other relevant features
Imported. Usually a differential diagnosis problem for
viral haemorrhagic fevers.
Yersiniosis
Control of human source
Statutorily notifiable if thought to be
the cause of food poisoning.
Cause
Yersinia enterocolitica; occasionally Y.
pseudotuberculosis.
Cases
Enteric precautions.
Reservoir
Gastrointestinal tract of many species of wild and
domestic animals and birds, usually asymptomatic.
Contacts
Clinical surveillance.
Exclusion
48 hours after first normal stool.
Microbiological clearance
None required.
Transmission
Contaminated food and water (organisms can
multiply in food at 4°C). Direct contact with
infected animals. Person-to-person spread may
occur. Particular association with raw pork and
pork products.
Other relevant features
Many cases in children present as abdominal pain
that mimics appendicitis. Not all strains are
pathogenic and Y. enterocolitica can be isolated
from asymptomatic individuals.
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Appendix 1b – Toxins
Chemical Food borne Illness
The list on the next few pages is a selection of foodborne illness caused by
chemicals. The list is not exhaustive, but attempts to give an idea of the wide variety
of ways in which chemicals in food can be implicated in poisoning episodes.
Examples of food being contaminated by chemicals are numerous. They may result
from:

The addition of too much of a chemical allowable in foods e.g. Sorbitol

Accumulation of a naturally occurring chemical e.g. Paralytic/diarrhetic shellfish
poisoning;

Accumulation of inorganic chemicals e.g. Heavy metal contamination of shellfish;

The addition of a non-allowable chemical e.g. Toxic oil syndrome;

Changes in manufacturing processes allowing a new chemical entity to be copurified with the final product e.g. Chemical contamination of tryptophan producing
the Eosinophilic-Myalgic syndrome;

Inadequate preparation of foodstuffs e.g. Kidney bean poisoning;

The accidental ingestion of toxic species of common foods e.g. Mushrooms;

Contamination with herbicides and pesticides which can occur if manufacturers’
instructions are not followed e.g. Anticholinesterase in insecticides; and

Malicious contamination.
Other routes of contamination can arise as a result of air borne release of chemicals.
For instance, following an explosion or a transport accident involving a crashed
tanker, direct chemical contamination of foods can take place e.g. growing
vegetables and stored grain. Investigations should take cognisance of food grown in
the surrounding environment.
The effects of chemical contamination of food may be acute or chronic. The
definition of acute is arbitrary, but generally refers to a latent time of hours before the
onset of symptoms. In acute episodes symptoms produces by chemical poisonings
can be similar to those produced by bacterial contamination and it can be impossible
to distinguish between them without laboratory investigation.
Chronic effects generally occur when the exposure is insidious and over a long time
period, although it is possible for the effects of single exposure to a chemical to
become manifest at a later date. Because of the insidious nature of chronic
exposure it is inevitable that many people will have been exposed before the
appearance of symptoms draws attention to the problems. Examples of chronic
exposure to chemicals that have produced disastrous effects are methyl mercury
contamination of sea food (Minimata Disease) and the toxic oil syndrome in Spain in
which illicitly refined rape seed oil was sold as edible oil.
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1. CAUSATIVE
AGENT(S)
Gonyaulax spp., producing saxitoxin
Illness
Paralytic shellfish poisoning (PSP)
Comments
Saxitoxins are produced by certain marine algae such
as Gonyaulax and Alexandrium species. In summer
months Alexandrium species, which are
dinoflagellate constituents of plankton, may multiply
in seawater with visible effects (eg. Red tides).
Filter feeding bivalve shellfish and some crustacea
consume these algae and can concentrate the
saxitoxins to hazardous levels.
Sources
Mussels, clams, oysters, scallops and crabs
Symptoms
Neurological symptoms – dizziness, tingling,
drowsiness, headache, muscular paralysis, even
respiratory paralysis and death – within a few hours
of ingestion. Occasional gastrointestinal symptoms.
Duration of illness
Dose dependent
Incubation period/onset
time
30 mins – 2 hours (dose dependant)
Diagnosis
PSP analysis by specialised laboratories. Action
level is 80μg/100g of shellfish
Control
Closure of shellfish beds
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2. CAUSATIVE
AGENTS(S)
Prorocentrum and Dinophysis spp., producing
okadaic acid
Illness
Diarrhetic shellfish poisoning (DSP)
Comments
Sources
Associated with red tides; however not all algal
blooms are red and their proliferation can be missed
as a consequence. These small dinoflagellate
plankton are consumed by shellfish which
concentrate the constituent toxic chemical known as
okadaic acid. Additional toxins designated DTX1,2,3, pectenotoxins 1-6 and yessotoxin.
Consumption of contaminated bivalve shellfish and
crustacea
Symptoms
Diarrhoea, nausea, vomiting and abdominal pain
Duration of illness
3-4 days
Incubation
period/onset time
30 minutes to not more than 12 hours
Diagnosis
Detection of DSP toxin in shellfish
Control
Closure of shellfish beds
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3. CAUSATIVE
AGENT(S)
Diatoms (phytoplankton) producing domoic acid.
Illness
Amnesic shellfish poisoning (ASP)
Comments
Filter feeding shellfish live off the small particles of
organic matter that they filter from the seawater,
including small plants or animals. Some of the small
plants (phytoplankton) contain toxins. When the
mollusc digests the toxic organism, the toxin is
retained largely in the digestive gland. The toxin is
water soluble and relatively rapidly cleared from most
shellfish but not others such as the Atlantic scallop
(Placopecten magellanicus), which appears to
accumulate the toxin over long periods of time. The
toxin is heat-stable and not destroyed by cooking.
Sources
Mussels, clams, scallops and anchovies
Symptoms:
Nausea, vomiting, abdominal cramps and diarrhoea;
headache. If severe, temporary or permanent brain
damage may occur. The syndrome is complex but the
most notable simple characteristic is a loss of shortterm memory, hence the toxin is sometimes called
Amnesic Shellfish Poison (ASP). Deaths may occur.
Duration of illness
Few days or longer in severe cases
Incubation period/onset
time
30 mins – 6 hours (dose dependant)
Diagnosis
Control
Domoic acid analysis by specialised laboratories
(HPLC or mouse bioassay). Action level is
40μg/100g of edible parts of shellfish
Closure of shellfish beds unless levels of toxin below
20 µg/g of edible parts of shellfish
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4. CAUSATIVE
AGENT(S)
Bacterial spoilage of scombroid (mackerel, tuna)
and other fish, producing histamine and related
chemicals
Illness
Scombrotoxin fish poisoning
Comments
Sources
Spread
Symptoms
Typically associated with consumption of fish, which
may contain concentrations of histamine and
histamine-like substances, but has also been caused
by other foods (eg Swiss cheese).
Spoilage bacteria which multiply in unrefrigerated
food
Spoiled fish that has been canned can pose a threat as
the toxin can resist canning temperatures.
Contaminated fish are not usually organoleptically
detectable.
Diarrhoea, flushing, headache, sweating sometimes
accompanied by nausea, abdominal pain, burning in
the mouth.
Duration of illness
6-24 hours
Incubation
period/onset time
10 mins – 2 hours (approximately)
Diagnosis
Control
Detection of excess levels of histamine in fish.
Recently it has been suggested that histamine is not
the best marker. However, other markers are not yet
in general use.
All open scombroid fish products should be kept
chilled, and canned fish should be pre-chilled to a
maximum of 5C before handling, to reduce the
likelihood of histidine-histamine conversion by
bacteria introduced during handling. All cans
(especially large catering cans) should be pre-chilled
before opening and handling product in preparation of
salads, mayonnaise mixes, etc. All made-up or mixed
scombroid fish products should be kept chilled
throughout their storage life until usage or disposal.
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5. CAUSATIVE
AGENT(S)
Heavy metals, for example: antimony, zinc, lead,
copper
Illness
Heavy metal poisoning
Sources
Symptoms
Consumption of contaminated food.
Antimony – acid foods stored in enamel
Zinc – acid foods stored in galvanised containers
Lead – food stored in lead, or contaminated with lead
accidentally
Copper – high acid foods stored in copper utensils
The association of gastrointestinal symptoms (bloody
diarrhoea, abdominal pain, nausea, vomiting and
upper gastrointestinal haemorrhage) with metallic
taste in the mouth.
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6. CAUSATIVE
AGENT(S)
Toxins from natural foods, for example;
1) phytohaemagglutinin, found in red kidney beans
2) Toxins, probably glycoalkaloids (solanine and
chaconine) in green or sprouting potatoes.
Illness
Natural toxin food poisoning
Comments
Toxigenicity
Sources
Symptoms
Raw red kidney beans must be soaked for at least 12
hours and then cooked thoroughly (boiled for at least 10
minutes). Canned red kidney beans can be eaten
without further cooking. Potato glycoalkaloids are not
destroyed by cooking or processing. Some doubts have
been expressed as to whether solanine is the causative
agent.
1) No data available
2) Adverse effects have been associated with the
ingestion of potatoes containing total glycoalkaloids
in excess of 200mg/kg.
1) Red kidney beans, butter beans and lentils
2) Green or sprouting potatoes
1) Nausea, vomiting, followed by abdominal pain and
diarrhoea
2) Unpleasant taste, bitterness, burning sensation in
mouth and throat, headache, diarrhoea and
vomiting, and feelings of general malaise
Duration of illness
3 hours – 6 days
Incubation
period/onset time
30 mins – 12 hours (approximately)
Diagnosis
Control
1) Detection of haemagglutinins in food
2) Glycoalkaloid concentrations should not exceed
200mg/kg. Identification of solanine best carried
out by specialised analytical laboratories.
Proper cooking of all bean varieties
Potatoes should be stored in a cool, dark place
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7. CAUSATIVE
AGENT(S)
Amanita phalloides (death cap), Amanita verna and
Amanita virosa, some Galerina and Lepiota species
Illness
Mushroom poisoning
Comments
These fungi contain a number of cyclopeptides and
amatoxins responsible for the poisoning that follows
consumption.
Toxigenicity
Variable
Symptoms
Colic, nausea, vomiting and diarrhoea. There may be a
brief period of apparent recovery that is followed by
liver and/or kidney failure. Death occurs in 20 –90% of
cases.
Duration of illness
1-30 days
Incubation
period/onset time
6 – 48 Hours
Diagnosis
Identification of causative agent in food, stomach
contents or stools. Detection of amatoxins in blood or
biological fluids. Monitoring patient hepatic function.
Treatment of cyclopeptide poisoning is complicated and
needs to be started rapidly. In all cases of mushroom
poisoning the possibility of cyclopeptide poisoning
must be excluded. Suspected cases of cyclopeptide
poisoning should be immediately referred to the
Regional Poisons Centre.
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8. CAUSATIVE
AGENT(S)
Amanita muscaria, Amanita pantherina containing
ibotenic acid and muscimol
Illness
Mushroom poisoning
Comments
Sources
Symptoms
No commonly eaten fungi are similar to these species
but A pantherina can be confused with A rubescens.
Ingestion likely to be accidental in children or as a
recreational drug in adults.
Fungi. Many other fungi also can cause poisoning eg
Inocytes, Cortinarius etc.
Initially similar to alcohol intoxication, progressing to
muscular twitches cramps and hyperkinesia. Visual
disturbances, hallucinations, a feeling of floating and
a feeling of superhuman strength ma occur. Children
may suffer from confusion, hysteria and seizures.
Duration of illness
<12 hour (approximately)
Incubation
period/onset time
30 mins – 3 hours (approximately)
Diagnosis
Symptomatology, fungi in stomach contents or stools
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9. CAUSATIVE
AGENT(S)
Aspergillus flavus and A parasiticus toxins,
aflatoxin
Illness
Aflatoxicosis
Comments
Sources
Symptoms
These fungi are found worldwide and grow on
practically any substrate.
Widespread in soil and air. Occur in some cereal
crops prior or harvest. Heavy rains and faulty
methods of storage also allow theses fungi to grow
especially in grain, peanuts and other nuts.
Vomiting, diarrhoea, fever, abdominal pain, jaundice,
coma, convulsions, hepatic and renal failure. Death
can occur 3 – 10 days after onset of symptoms.
Aflatoxins are also carcinogens.
Duration of illness
>10 days
Incubation
period/onset time
8 hours or longer
Diagnosis
Control
Isolation of fungi, microscopy, extraction, separation,
chromatography, spectrophotometry
Crop management, control of moisture during food
storage.
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10. CAUSATIVE
AGENT(S)
Anticholinesterase insecticides, including the
organophosphorus and carbamate insecticides
Illness
Pesticide food poisoning
Comments
Symptoms
Diagnosis
Although several groups of pesticides have given rise
to acute poisoning in various parts of the world, many
of these poisonings are due to suicide or accident, and
few are caused by food contamination. Aldicarb was
responsible for outbreaks of food-borne illness in the
USA, Canada and Ireland.
Accumulation of the neurotransmitter acetylcholine,
causing symptoms such as bradycardia, blurred
vision, dyspnoea and muscle fasciculation. In severe
cases convulsions may occur. In mild oral poisoning
the most prominent symptom is stomach pain, which
is often described as cramp-like. Specific antidotal
treatment is available: atropine is effective in both
organophosphorus and carbamate poisoning; in
addition in organophosphorus poisoning, pralidoxime
mesylate should be administered.
Diagnosis is based upon the characteristic clinical
signs and measurement of plasma and erythrocyte
cholinesterase levels.
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Revised September 2011
Appendix 1c – Factsheets, links and policies
Health Protection Legislation (England)
Guidance 2010
http://www.dh.gov.uk/prod_consum_dh/gro
ups/dh_digitalassets/@dh/@en/@ps/docum
ents/digitalasset/dh_114589.pdf
London Infectious Disease Outbreak
Management Plan. (latest version can be
found in the HPA website using the search
box)
http://www.hpa.org.uk/AboutTheHPA/What
TheHealthProtectionAgencyDoes/LocalSer
vices/London/RegionalPublications/Infectio
nControl/londinfdiseaseoutbreakmgmentpla
n/
Food and Environmental Questionnaire
S:\Reactive
Folder_NEW\Gastro - Katie & Simon\Questionnaires and
HPA Lab Guidebook for Environmental
Health Officers, Consultants in
Communicable Disease
Control and Primary Care Groups
Barts and the
London HPA lab.pdf
Aeromonas
general D&V
leaflet.doc
Bacillus cereus / subtilis
general D&V
leaflet.doc
Campylobacter
Campylobacter
London factsheet for public March 2011.doc
Clostridium perfringens
general D&V
leaflet.doc
Cryptosporidium
o Policy
o Questionnaire
o Factsheet
S:\Reactive Folder\
Cryptosporidium
London fact sheet for Questionnaires\Cryptosporidiosis
public March 2011.doc
case questionnaire r
S:\Reactive Folder\
Policies\Cryptosporidium policy NE London_2010.doc
Giardia
Giardia London
factsheet for public March 2011.doc
Salmonella non- Typhoid or Paratyphoid
Salmonella London
factsheet for public march 2011.doc
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Revised September 2011
Shigella non-sonnei
Shigella London
factsheet for public March 2011.doc
Taenia solium
(worms)
(link to NHS information)
http://www.nhs.uk/conditions/Tapeworm
-infections/Pages/Introduction.aspx
Vibrio non-cholera
Viral gastroenteritis
Yersiniosis
general D&V
leaflet.doc
Norovirus.doc
Rotavirus
Factsheet_TM.doc
general D&V
leaflet.doc
Hepatitis A
o
Policy
o
Questionnaire
o
Factsheet
Hepatitis A policy
July 2010.doc
S:\Reactive Folder\
Questionnaires\Hepatitis A London 2011 V3 0.
S:\Reactive Folder\
Factsheets\Hepatitis A.doc
Legionella
o
Policy
o
Questionnaire
o
Factsheet
Legionnaires' Disease S:\Reactive Folder\
Policy_2010.doc
Questionnaires\Legionella Questionnaire(elect
S:\Reactive Folder\
Factsheets\Legionnaires.doc
Listeria Monocytogenes
o
Policy
o
Questionnaire
o
Factsheet
Listeria 2010.doc
S:\Reactive Folder\
Questionnaires\Listeria trawling questionnaire
S:\Reactive Folder\
Factsheets\Listeria.doc
Salmonella Typhoid and Paratyphoid
o
Questionnaire
o
Operational guidance
o
Factsheet
o
Warn and inform letter
S:\Reactive Folder\ S:\Reactive Folder\
Policies\Typhoid and paratyphoid
Policies\Typhoid
policyand
andparatyphoid
supportive documents
policy and su
J
S:\Reactive Folder\ S:\Reactive Folder\
Policies\Typhoid and paratyphoid
Policies\Typhoid
policyand
andparatyphoid
supportive documents
policy and su
J
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Shigella non Sonnei
o
Policy
o
Factsheet
S:\Reactive
S:\Reactive Folder\
Folder_NEW\Shigella -Factsheets\Shigella
Vicky\Shigella PolicyLondon
Marchfactsheet
2012.doc for publ
S:\Reactive
Folder_NEW\Shigella - Vicky\March 2012_Enhanced Shig
VTEC O157
o
o
o
o
Operational manual
Supporting evidence
Questionnaire
Factsheet
VTEC opertaional
VTEC Support
manual Feb 2011.pdf Document - Background evidence for PH Mana
S:\Reactive Folder\ S:\Reactive Folder\
Questionnaires\VTEC Questionnaire
Factsheets\E.Coli
- electronic
0157 fact
version
sheet-Nov08.doc
2011.doc
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