14- HCAI_Antibiotic_resistance_2011 - ECDC

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Health Care Assiciated Infections and
Antibiotic Resistance:
an increasing threat to Patient Safety in
Europe
Aftab Jasir, European Centre for Disease Prevention and Control (ECDC)
European public health microbiology training program (EUPHEM)
Objectives of the lecture
To learn and understand about:
 Basic of antibiotics and resistant among
bacteria
 Health care associated infections
 Relevant terminologies
Story of glory
1945
Fleming, Florey and Chain
Antibiotics
5
Antimicrobial drugs
Natural antibiotics
Synthesized antibiotics
6
Natural antibiotics
Penicillium notatum
7
Knowledg about killing
 Do we need to use
antibiotics for killing of
pathogens?
8
Modern medicine is not possible without
effective antimicrobials
Hip replacement
Organ transplants
Cancer chemotherapy
Intensive care
Care of preterm babies
Terminology
Antiseptics
• Topical substances (e.g. skin)
• e.g. iodine or 70% alcohol
• “reduce” bacterial load
10
Antibiotics
• Selectively toxic for bacteria
• bactericidal (killing)
• bacteriostatic (growth inhibition)
• no harm to patient (???)
12
Prophylaxis
13
Minimal inhibitory concentration/
minimal bactericidal concentration
(MIC/MBC)
 lowest level stopping growth/killing
e. g. zone of inhibition around a disk
14
MIC/MBC
15
Most important targets in bacteria
1. Attack bacterial cell wall synthesis.
2. Interfere with protein synthesis.
3. Interference with nucleic acid synthesis (RNA and DNA)
4. Inhibition of an essential metabolic pathway that exists in the
bacterium but does not exist in the host
5. Membrane inhibition or disruption
doesn't work too well because of the similarities between and
bacterial membranes.
16
17
Drug usage = Drug resistance
Basis of Antibiotic Resistance
 The antibiotic resistance is guided by Genomic changes
 Spread of R plasmids or other genetic elements among the
Bacteria
 Do remember Antibiotics are used in veterinary
medicine
 The discovery of antibiotic resistance was discovered with
spread of R plasmids from animal sources
Plasmids and Transposons
RTF
Tn 21
Tn 10
Tn 9
R
determinant
Tn 8
Superbugs
Multi drug-resistant
acquired non-susceptibility
to at least one agent in three
or more antimicrobial categories
Extensively drug-resistant
non-susceptibility to at least
one agent in all but two
or fewer antimicrobial
categories
Pandrug-resistance (PDR)
non-susceptibility to all agents
in all antimicrobial categories
Welcome to the hospital!
Bugs are waiting for you!!!
NIIIIIICE! I am getting something good here
Terminology
 Nosocomial
• Traditional meaning “originating in hospital”
 Hospital-acquired/associated
 Healthcare-acquired/associated
 HAI
or
NI
or HCAI
Definition
An infection occurring in a patient/staff/visitor in a
healthcare facility not present or incubated at the
time of admission.
- includes infections that do not become apparent until
after discharge and occupational infections among staff
of the facility
Healthcare-associated infections, antimicrobial resistance: Overlapping, but not identical
Healthcareassociated
infections
Antimicrobial
resistance
Community-acquired
infections
Burden of Healthcare-Associated Infections
and Multidrug Resistance
(preliminary estimate)
 Healthcare-associated infections (HCAI)
• approximately 4 million per year
• approx. 37,000 directly attributable deaths each year
 Multidrug-resistant bacteria
• approximately 1/2 of the deaths attributable to HCAI
are due to the 7 most common multidrug-resistant bacteria
in the 4 main types of HCAI: bloodstream infection,
pneumonia, skin and soft tissue infection, urinary tract
infection
This is an underestimate!
Source: Suetens C & Monnet DL, ECDC
(preliminary estimate)
30
Risk factors
 External/none host
• Catheters and other
invasive devices
• Surgeries
• Invasive procedures
• Antibiotic exposure
• Inadequate staff and
overcrowding
 Internal/Host
•
•
•
•
•
Extremes of age
Immune status
Illness severity
Comorbidities
Colonization status
New challenges
http://ecdc.europa.eu/en/publications/Publications/Forms/ECDC_DispForm.aspx?ID=740
Challenges in developing Case-Definitions for
HAI
Assumptions:
 >48 or >72 hours after admission
 Not incubating at the time of admission
 Can manifest after discharge
 Acquired in healthcare setting
 Use both clinical and lab criteria
Examples of potential for misclassification
Case 1
 80 y.o. patient, multiple medical problems, lives at
home, visited by grandchildren who have colds
 2 days later, admitted for hip fracture
 4 days after admission she develops RSV (respiratory
syncytial virus) pneumonia
What you think?
Examples of potential for misclassification
Case 2
 55 y.o. patient, admitted for work-up and
management of chest pain, cared for by healthcare
worker taking care of another patient who has MRSA
 Discharged after 2 days in hospital
 Develops an MRSA soft tissue infection 3 weeks later
while in the community
What now???
Incubation periods






C.difficile
MRSA
VRE
Influenza
RSV
Norovirus
unknown
unknown
unknown
1-4 days
2-8 days
24-48 hours
Conclusions
 There are always outbreaks going on at the
hospitals. However they might not be
detectable
 Hospitals are a suitable place for outbreak
investigation
 It is not always easy to define the cases
 Outbreaks agents circulating frequently.
Therefore you need good microbiological
evidence to confirm your cases.
Hands are the most common public
transport of microorganisms
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