Foodborne Disease Outbreak
Investigation Team Training:
Module 7 – Multijurisdictional
Outbreaks
Multijurisdictional outbreaks
1
Module Learning Objectives
At the end of this module, you will be able to
1. Discuss recent shifts in the nature of foodborne
disease outbreaks.
2. List indicators that suggest an outbreak is likely
to involve cases from multiple jurisdictions.
3. Describe federal public health agencies likely to
participate in multijurisdictional investigations.
4. List clues that an outbreak might be due to
intentional contamination.
5. State whether the local incident command
system is activated during an outbreak response
in your jurisdiction.
Multijurisdictional outbreaks > Learning objectives
2
Traditional Outbreak Scenario
Focal outbreak
• Caused by local food handling error (endpoint
contamination event)
• Large number of cases in one jurisdiction
• Detected by affected group
• Local investigation
• Local solution
Multijurisdictional outbreaks
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Traditional Outbreak Scenario (cont’d)
Farm
Production
Processing
Distribution
Final preparation
and cooking
Localized
cases
Multijurisdictional outbreaks
Problematic food
safety practices
4
New Outbreak Scenario
Dispersed outbreak
• Caused by industrial contamination event
(during production, processing, or distribution)
with a widely distributed food
• Small numbers of cases in many jurisdictions
• Detected by pathogen-specific surveillance
with subtyping
• Multijurisdictional
investigation
• Solution that has broad
implications
Multijurisdictional outbreaks
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Diffuse Outbreak Scenario (cont’d)
Production
Problematic food
safety practices
Farm
Processing
Distribution
Final preparation
and cooking
Dispersed cases
Multijurisdictional outbreaks
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E. coli O157:H7 and Cookie Dough
• Cluster of E. coli O157:H7 detected by PulseNet
with cases from 13 states
• No commonalities through initial case interviews;
open-ended interviews in WA revealed 5 of 5
cases ate raw cookie dough
• Multistate case-control study linked illness to
Brand X cookie dough
• Non-outbreak STEC
isolated from cookie
dough and flour supplier
• 77 cases in 30 states
Multijurisdictional outbreaks
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Significance of Multijurisdictional
Outbreaks

• Small proportion (2%) of reported foodborne
outbreaks are multistate
• Disproportionate public health impact
− 7% of outbreak-related illnesses
− 31% of outbreak-related hospitalizations
− 34% of outbreak-related deaths
− 40% of E. coli O157:H7 and 25% of
Salmonella and hepatitis A outbreaks
Source: CDC, National Foodborne Disease Outbreak Surveillance
System, unpublished data (2006-2010)
Multijurisdictional outbreaks
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Significance of Multijurisdictional
Outbreaks (cont’d)
Number of outbreaks
Multistate foodborne outbreaks, 1989-2008
Year of Report
Source: CDC, National Foodborne Disease Outbreak Surveillance System
Multijurisdictional outbreaks
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Reasons for Increase
• Centralized production and wide distribution of
food products
• Globalization of food supply
• Increased detection of outbreaks through
– Improved surveillance efforts
– Subtyping of causative agents
– Information sharing
Multijurisdictional outbreaks
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Local Significance of Multijurisdictional
Outbreaks
• “Local” outbreak may herald a national or
international event.
Multijurisdictional outbreaks
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Listeriosis and Cantaloupe
• Seven cases of listeriosis reported from CO
• All had eaten cantaloupe in month before illness
• Cases in other states detected through PulseNet;
comparisons of outbreak-related and non-outbreak
related listeriosis cases confirm cantaloupe link
• Traceback converges on
CO producer that
shipped cantaloupe to
24 states
• 146 cases from
28 states
Multijurisdictional outbreaks
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Multijurisdictional Outbreak Indicators
• Implicated food contaminated before point of
service and is
– Commercially distributed, processed, or readyto-eat item
– Fresh produce item
– Ground beef in E. coli O157:H7 outbreak
• Illnesses linked to multiple food-service
establishments
• Molecular subtype of causative agent matches
agent associated with outbreaks in other locations
• Exposed persons have subsequently dispersed
Multijurisdictional outbreaks
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
Class Question
Which of the following outbreaks are likely to involve
cases residing in multiple jurisdictions?
Multiple
Illness linked to food safety problem at
elementary school cafeteria
jurisdictions
No
Outbreak associated with national brand
food; no local contributing factors
identified
Yes
Cases linked to food purchased from
several different restaurants in one city
Yes
Outbreak linked to food served on airline
flight
Yes
Multijurisdictional outbreaks
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Local Significance of Multijurisdictional
Outbreaks
• “Local” outbreak may herald a national or
international event.
• Local jurisdictions will need to coordinate
investigation efforts with other local, state,
and federal partners.
Multijurisdictional outbreaks
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Federal Public Health Agencies
• Centers for Disease Control and Prevention (CDC)
- Non-regulatory agency that focuses on disease
surveillance, outbreak detection, and investigation
• U.S. Department of Agriculture/Food Safety and
Inspection Service (USDA/FSIS) - Regulatory
agency that oversees safety of meat, poultry, and
pasteurized egg products
• U.S. Food and Drug Administration (FDA) Regulatory agency that oversees safety of most
foods except meat, poultry, and pasteurized egg
products
Multijurisdictional outbreaks > Federal public health agencies
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Federal Agency Contributions to
Outbreak Investigation
•
•
•
•
Leadership and coordination
Expertise and experience
Laboratory testing
Other resources (e.g., manpower, educational
materials)
• Public health regulatory authority over certain
control measures (e.g., recalls)
Multijurisdictional outbreaks > Federal public health agencies
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When to Involve Federal Agencies
• Outbreaks associated with
– Cases from multiple states (or countries)
– Commercially distributed food contaminated
before point of service
– Highly pathogenic or unusual causative agent
– Large numbers of cases that require
additional resources to investigate
– Intentional contamination suspected
• Request for assistance through state
epidemiologist
Multijurisdictional outbreaks > Federal public health agencies
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Local Significance of Multijurisdictional
Outbreaks
• “Local” outbreak may herald a national or
international event.
• Local jurisdictions will need to coordinate
investigation efforts with other local, state, and
federal partners.
• Local jurisdictions may be asked to urgently
investigate one or a few cases that are part
of a larger outbreak despite their apparently
small local impact.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (1)
• March 1: NY State notifies CDC of 4 persons
infected with Salmonella Bareilly with unusual
PFGE pattern.
Vigilant state health
department quickly brings
attention to problem.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (1)
• March 1: NY State notifies CDC of 4 persons
infected with Salmonella Bareilly with unusual
PFGE pattern.
• March 2: PulseNet shows 11 persons in 7 states
with the same pattern. CDC initiates multistate
investigation and holds first conference call.
Rapid communication ensues between
local, state, and federal public health
partners; states share case information
during conference call and are asked to use
same hypothesis-generating questionnaire.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (1)
• March 1: NY State notifies CDC of 4 persons
infected with Salmonella Bareilly with unusual
PFGE pattern.
• March 2: PulseNet shows 11 persons in 7 states
with the same pattern. CDC initiates multistate
investigation and holds first conference call.
• March 8: Interviews of 8 ill persons reveal 7 ate
seafood and 5 ate sushi before illness.
Since most states have only 1-2
cases, comparison of case
information across states is
critical for hypothesis generation.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (2)
• March 8-13: TX and WI each
report cluster of unrelated cases
who ate a same Japanese
restaurant. Focused hypothesis
generating questionnaire deployed.
New hypothesis-generating questionnaire
to be used by all investigators focuses on
sushi; restaurant clusters allow initiation of
traceback studies.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (2)
• March 8-13: TX and WI each
report cluster of unrelated cases
who ate a same Japanese
restaurant. Focused hypothesis
generating questionnaire deployed.
• March 15: FDA begins receiving supplier and
invoice data.
Local and state staff collect invoices,
receipts, and bills of lading from food
establishments associated with clusters.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (2)
• March 8-13: TX and WI each
report cluster of unrelated cases
who ate a same Japanese
restaurant. Focused hypothesis
generating questionnaire deployed.
• March 15: FDA begins receiving supplier and
invoice data.
• March 16-27: WI, CT, and MD report clusters that
ate sushi from same store/restaurant; based on 20
case interviews, >90% ate sushi, primarily spicy
tuna.
States search for cases related to outbreak and
complete interviews; link to sushi strengthens.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (3)
• March 29-April 9: Comparison of meal receipts at 4
restaurants shows 84% of case meals and 37% of
meals of other customers contained spicy tuna.
Local and state staff undertake study
at restaurants linked to outbreak.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (3)
• March 29-April 9: Comparison of meal receipts at 4
restaurants shows 84% of case meals and 37% of
meals of other customers contained spicy tuna.
• April 10: WI reports 5 Salmonella Nchanga
infections in same states as S. Bareilly cases. One
ate at same restaurant as S. Bareilly case; one was
chef at restaurant where S. Bareilly case ate.
Continued sharing of
information brings new twist
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (3)
• March 29-April 9: Comparison of meal receipts at 4
restaurants shows 84% of case meals and 37% of
meals of other customers contained spicy tuna.
• April 10: WI reports 5 Salmonella Nchanga
infections in same states as S. Bareilly cases. One
ate at same restaurant as S. Bareilly case; one was
chef at restaurant where S. Bareilly case ate.
• April 13-14: Producer is identified,
recalls yellowfin tuna from
processing facility in India; CDC
Recall based on data
and FDA warn public.
Multijurisdictional outbreaks
collected by states
and analyzed by FDA.
28
Anatomy of a Multijurisdictional Outbreak (4)
• April 19-24: FDA conducts inspection at processing
facility noting several seafood HACCP deficiencies
and sanitation concerns.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (4)
• April 19-24: FDA conducts inspection at processing
facility noting several seafood HACCP deficiencies
and sanitation concerns.
• April 24-26: S. Bareilly is isolated from recalled
tuna and spicy tuna roll made with recalled tuna;
outbreak strains of S. Bareilly and Nchanga found in
unopened packages of
yellowfin tuna product
from producer.
Multijurisdictional outbreaks
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Anatomy of a Multijurisdictional Outbreak (4)
• April 19-24: FDA conducts inspection at processing
facility noting several seafood HACCP deficiencies
and sanitation concerns.
• April 24-26: S. Bareilly is isolated from recalled
tuna and spicy tuna roll made with recalled tuna;
outbreak strains of S. Bareilly and Nchanga found in
unopened packages of
yellowfin tuna product
from producer.
• Total 425 cases
from 28 states
and D.C.
Multijurisdictional outbreaks
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Role of State and Local Jurisdictions in 
Multijurisdictional Outbreaks
• Notify others of local outbreaks.
• Be aware of outbreaks in other jurisdictions.
• Search for local cases/clusters associated with
multijurisdictional outbreak.
• Participate in hypothesis generation.
• Perform tasks (e.g., interview cases, undertake
studies) as agreed upon.
• Collect paperwork to support traceback
investigations by federal agencies.
Multijurisdictional outbreaks
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Intentional Contamination
Multijurisdictional outbreaks
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Intentional Contamination of Food
• Few documented incidents
• Food vulnerable target
• Vigilance and heightened awareness regarding
tampering with food supply are essential
Multijurisdictional outbreaks > Intentional contamination
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Nicotine Poisoning and Ground Beef
• Supermarket customers in MI complain of burning
of the mouth, nausea, vomiting, and dizziness
following consumption of ground beef purchased
on certain dates
• Supermarket recalls 1,700 lbs. beef from out-ofstate processor that was ground at the store
• Samples of ground beef found positive for nicotine
• Local health department
identifies over 90 cases
• Employee indicted by grand
jury
Multijurisdictional outbreaks > Intentional contamination
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Public Health Clues

• Likely to mimic unintentional foodborne outbreak
Env’t Health
Unusual food
Contamination
without clear
natural pathway
Contamination at
unexpected step
in production
Evidence of
tampering
Multiple exposure
sites or foods with
no apparent link
Epidemiologic
Large number of
cases in short time
Multiple labs or
states in short time
Setting of large
exposure numbers
Unusual illness,
treatment response,
high hospitalization
and death rate
Unseasonal pattern
Laboratory
High concentration
of causative agent
in implicated food
Unusual agent
Unexpected agent
for food
Combination of
agents
Isolates from
unrelated foods
Multijurisdictional outbreaks > Intentional contamination
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Nicotine Poisoning and Ground Beef (cont’d)
Hints of intentional contamination
• Nicotine as a contaminant of ground beef
• 300 mg/kg of nicotine in implicated ground beef
• Contamination limited to single store
• Nicotine-containing pesticides not used at store
• Source of nicotine thought to be Black Leaf 40,
an insecticide formulation discontinued in 1992
Multijurisdictional outbreaks > Intentional contamination
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Investigation of Intentional Contamination
• Follows same approach as for all outbreaks until
intentional contamination suspected
• Then everything changes!!!
– Different partners with different objectives
– Added steps (e.g., parallel investigation by
law enforcement)
– Special issues (e.g., safety of team members,
proper handling of specimens, capacity of
laboratory to test for unusual agents)
• Importance of developing working relationship
with possible partners BEFORE incident occurs
Multijurisdictional outbreaks > Intentional contamination
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Incident Command System
Multijurisdictional outbreaks
39
Incident Command System (ICS)
• Management system that helps multiple agencies
work together
• Supports and coordinates necessary activities
and communications
• Has operating rules and processes
Multijurisdictional outbreaks > Incident Command System
40
Salmonella and Public Water System
•
•
•
•
Salmonella outbreak in Alamosa, Colorado
442 illnesses and one death
Source determined to be public water system
Colorado Safe Drinking Water program focused
on correcting problems with public water system
• ICS helped to manage others aspects of response
including
− Bulk water delivery
− Public notification of
advisories and updates
− Interagency coordination
Multijurisdictional outbreaks > Incident Command System
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Activation of ICS in Outbreak Response?
• Determined by agency/jurisdiction
− Some jurisdictions use ICS extensively
− Others do not
• Triggers for involvement should be decided in
advance
• Necessary integration of ICS into response
planning and team training, if decision is made to
activate system under certain circumstances
Multijurisdictional outbreaks > Incident Command System
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Class Question
1. Is the Incident Command System (ICS)
activated in your jurisdiction when a foodborne
outbreak is detected?
2. If so, under what circumstances is it activated?
Multijurisdictional outbreaks > Incident Command System
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Quick Quiz
Multijurisdictional outbreaks
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Quick Quiz
1. Which of the following is a likely reason for the
increase in multijurisdictional outbreaks in
recent years?
A. Food produced in the United States is less
safe than it used to be
B. Improved ability to link cases of foodborne
illness due to subtyping efforts
C. Antibiotic use in livestock
D. Increased interest in locally produced foods
sold through farmer’s markets
Multijurisdictional outbreaks
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Quick Quiz
2. All of the following characteristics suggest that
cases associated with a local outbreak might
reside in multiple jurisdictions EXCEPT
A. Implicated food was widely distributed.
B. Contributing factors were found at the
implicated restaurant during the
environmental health assessment.
C. Illness among cases was linked to multiple
restaurants.
D. Outbreak was linked to an event that drew
participants from many states.
Multijurisdictional outbreaks
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Quick Quiz
3. Which of the following is a likely contribution of
federal public health agencies to a multijurisdictional foodborne outbreak investigation.
A. Expertise and experience
B. Resources such as laboratory testing
C. Leadership and coordination
D. All of the above
Multijurisdictional outbreaks
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Quick Quiz
4. Only uncommon microbial agents are
associated with intentional outbreaks.
A. True
B. False
Multijurisdictional outbreaks
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Quick Quiz
5. Which of the following statements about the
incident command system (ICS) is correct?
A. The health department should not activate
the ICS until the situation reaches a crisis.
B. ICS operating rules and processes can help
multiple agencies work together efficiently
and effectively.
C. It is recommended that the local ICS be
activated in all foodborne outbreaks.
D. Involved agencies will be familiar with public
health and foodborne diseases.
Multijurisdictional outbreaks
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