How I deal with an outbreak? Prof Bertrand SOUWEINE Medical ICU Clermont-Ferrand France ISICEM March 2009

“The occurrence in a defined community or region, of cases of an illness with a frequency clearly in excess of normal expectancy”

VRE is an emergent pathogen responsible for outbreaks

Outbreak detection: Initial Call March 2004, a 70-yr old male admitted to MICU acute respiratory failure urine analysis positive for VRE faecium. January 2004 emergency repair of ruptured abdominal aneurism multiple successive units admission: surgical ICU, surgery, rehabilitation center

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

First step: verify the diagnosis Misdiagnosis Laboratory error

VRE from samples were isolated on Columbia agar (no enrichment broth) Biochemical identification and antibiotic testing were performed with Vitek 2 card. AB susceptibility was interpreted according to French national guidelines Glycopeptide resistance studied by determining MIC (E-test, AB biodisk) First step: verify the diagnosis

First: think prevention

Initial measures to limit VRE spread Reinforcement of contact precaution for VRE carrier care Strong recommendation for use of alcohol- based hand-rub (ABH) Wearing gloves and single use gown when entering the room Daily environmental cleaning Tracking contact patients for screening Briefings for HCWs with regular updates IC nurses verify the implementation of control measures

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

From January to March VRE faecium identified from clinical samples In 3 different wards In 2 of the 3 sites Confirm the outbreak

Over the 4 preceding years only 2 VRE per yr Despite –No recent change in reporting procedures –No recent change in diagnostic procedures Second step: Confirm the outbreak

VRE control committee Chief executive (hospital administrator) 1.Head physician of the infection control policy (CLIN) 2.Chief executive of the medical staff 3.Infection control physicians and nurses 4.Infectious diseases physicians 5.Hospital microbiologist 6.Director of nursing services 7.Representatives from the major clinical specialties and from the pharmacy.

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

Define, identify, and count cases Case definition colonized patient: VRE identified from surveillance cultures infected patient: VRE identified from clinical sample VRE carrier: patient either colonized or infected with VRE

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

Location 1 Location 2 Location 3

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

Factors associated with P <0.05 in multivariate analysis

1.Verify the diagnosis 2.Confirm the existence of an outbreak set up a control committee 3.Identify and count cases establish case definition 4.Orient data in terms of time, place and person 5.Formulate and test hypotheses 6.Conduct animal/environmental studies to identify source of the agent 7.Write a report What are the steps in an outbreak investigation? Implement control and prevention measures

Control measures focused on hand hygiene and reinforcement of contact precautions alcoholic-based solution for hand hygiene Outbreak detection antibiotic restriction 8.5 L/1000 days 17.8 L/1000 days single rooms, bed closures, admission restriction, regular meetings routine admission/weekly/discharge screening policy in wards where the outbreak was active decrease in the time for obtaining bacteriological swab results

Location 1 Location 2 Location 3 monthly rectal screening samples Colonized, N=163 Infected, N=57 urine culture, N=29, blood culture, N=9

The wards most affected by VRE Location 2 Location 3 Location 2Location 3

Vancomycin MIC > 256 mg/l Teicoplanin MIC ≥ 32 mg/l PCR analysis identified: VanA All of the strains expressed a high level of resistance to glycopeptide

Representative pulsed-field gel electrophoresis (PFGE) patterns of SmaI-restricted chromosomal DNA from VRE isolates

September Rectal swab screening in 1171 patients Colonization, N=2 (0.17%) ICU (N=1), LTCF (N=1) Large prevalence survey

outbreak committee with authority multidisciplinary collaboration multifaceted approach alcohol-based hand hygiene disinfection strong reinforcement of hygiene measures strict screening policy Conclusion

Acknowledgements Claire Aumeran Olivier Baud Bruno Coignard Olivier Lesens Ousmane Traoré Infection control nurses C-CLIN Sud-Est