Outbreak investigation of nosocomial infections

Transcription

1 Definitions Outbreak investigation of nosocomial infections School of Public Health, HSUM March 2012 Walter Popp, University Clinics Essen, Germany Epidemia increased number of cases, limited in time and area Endemia increased number of cases, limited in area, unlimited in time Pandemia epidemia worldwide limited in time, unlimited in area Outbreak epidemia, usually not so big 1 2 Outbreak Infection Prevention Law (Germany), 6 (3) Cumulated appearance of nosocomial infections for which an epidemic connection is presumed or proven. Epidemic means increase of communicable disease, limited in room and time. Infections means sickness, not contamination or carrier. Infections to think about an outbreak even in single cases Infections during hospital stay: Legionellosis, aspergillosis, pertussis, infection by Streptococcus pyogenes (group A), conjunctivitis epidemica, scabies, RSV (respiratory syncytical virus), influenza

2 Infections which might be an outbreak in case of 2 or more patients Infections with similar species and resistogram. Infections with uncommon pathogens. Sepsis with similar pathogens (similar species and, eventually, resistogram). Infections by blood-borne pathogens (eg HIV, HBV, HCV). Pathogens of gastroenteritis (eg Clostridium difficile, rotavirus, norovirus, salmonellosis). Infections which might be an outbreak in case of 2 or more patients Multiresistant pathogens: Meticillin resistant Staphylococcus aureus (MRSA) Vancomycin resistant enterococci (VRE) Streptococcus pneumoniae Escherichia coli Klebsiella spp. Enterobacter cloacae Citrobacter spp. Serratia marcescens Pseudomonas aeruginosa Stenotrophomonas maltophilia Burkholderia cepacia Acinetobacter baumanii Candida spp. 5 6 Pathogens and way of transmission some examples Need for a good quality microbiologic laboratory! Hepatitis B: Blood! No need to think about surfaces as transmission factor. Sharp handling mistakes! Infection from staff? Salmonellosis: Food. Kitchen? Could chain working? Food distribution on ward? Pseudomonas: Water system. Sinks? Ventilation/moistening. Escherichia coli: Gastrointestinal tract. Hands and handling. Surface and cleaning. Step 1: Decision about outbreak Hints from ward/department and/or microbiologic lab. In case of suspicion, instantly give information to hospital hygiene. Hospital hygiene has to get informations on respective ward. Decision about outbreak made by head of department/ward and hospital hygiene, At least information of medical director of hospital (or include him/her in decision making), Reporting to state authorities? depends on law. Helpful informations: Which infections? Which pathogens? Which patients? Are there associations in rooms and time? Additionally persons involved? Eg staff Are technical systems or media (water, air, food) a possible source of infection? 7 8 2

3 Step 2: Actual situation and decision making about an outbreak management team If you have experience in some outbreaks and pathogens and the outbreaks seem to be small, you can handle on level of ward with hospital hygiene: MRSA, norovirus, rotavirus, adenovirus (infectious conjunctivitis). In that case, ward and hospital hygiene should have close contact every day, also decide about end of outbreak. Such a simple handling usually is not possible in case of: High number of patients with respective infection in short time, very dangerous pathogen (eg EHEC, tuberculosis, avian influenza, SARS), ward/department with highly susceptible patients, eg neonatology, hematology/oncology. In that case step 3. Also if simple outbreak cannot be stopped. 9 Step 3: Start of outbreak management team In case of big and risky outbreaks building of an ad hoc group: outbreak management team. Members: Medical director of hospital, director of nurses, hospital hygiene, microbiology/virology lab, media officer, cleaning department/unit, eventually state authorities, link doctors and nurses, works doctor, pharmacy, transportation unit, function departments (eg physiotherapy). It may be easier to open the group for other interested and involved staff (eg radiology) less need to give informations or have discussions. Usually meetings daily, may change with time. Every meeting needs a minutes of the meeting which has to be distributed in short time. Have a list of all wards and patients involved, updated at least every day. 10 Step 4: Investigations at the ward and decisions what to do Additional investigations on the ward, by hospital hygiene, eg: Real work done according to hygiene plan (standard procedures)? Design and construction reality, quality of cleaning, quality of reprocessing of medical devices, hand hygiene. Step 5: Decision about interventions Decision about interventions, decision might be made in outbreak management team. Eg: Information and training of staff, disinfection measures, isolation of patients, screening, stop for taking up new patients, closing of ward for some time. Documentation of all decisions

4 Step 6: Finding the origin of infection Different means might help: Thorough visit to ward, detailled control of all handling and doing, environmental investigations. Microbiologic investigations can help, eg: Contact patients, staff, water, air, food, drugs, hand contact areas, instruments and other medical products. Step 7: Finishing of outbreak, evaluation Outbreak management team makes decision about end of outbreak. Retrospective analysis of outbreak and written documentation, Prepared most of all by hospital hygiene. Make conclusions for improvements and similar situations. Store bacteria you found in case you need more investigations (eg genotype). Ongoing opinion making about results, get a hypothesis about origin and try to varify it, get a final result and conclusion

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7 25 26 ICU: outbreak of Acinetobacter 4MRGN (panresistant) Patient 1 2 weeks later patients 2 and 3 1 week later patient 4 Environmental investigations (contact plates): 25 % positive

8 > 20 cfu, at least 2x cfu, at least 1x > 20 cfu, at least 2x cfu, at least 1x > 100 cfu

9 MRSA on ICU Patients with nosocomial MRSA (time of detection) MRSA on ICU Staph. aureus MRSA known MRSA patient Investigation n n MRSA n not in MRSA room Environment rooms Environment 14 days anteroom later 1 hall Staff > 60 4 Environment 2 months later Results of contact plates: 9 x MRSA 3 x Staph. aureus

10 EHEC (Entero-hemorrhagic E. coli)

11 EHEC Gowns and gloves Hand disinfection Isolation until 3 negative stool probes in distances of 1-2 days Limited opening of an infection ward Outbreak at University Clinics Giessen, Neonatology : At least 28 babies with Klebsiella oxytoca sepsis. More staff from a staff pool Outbreak management team Staff claiming about smelling disinfectant concentration of disinfectant reduced from 0.5 % to 0.25 % Minutil (Formaldehyd) hygiene audit: Bottles of infusions were disinfected not by alcohol but by surface disinfectant. It was seen that infusion bottles were disinfected in bucket with surface disinfectant. Microbiologic lab: All isolates of the bacteria were identical. All environmental investigations were negative. Bacteria was found by chance in a bucket with disinfectant, 0.25 % solution (identic genotype). Bacteria was growing gin 0.25 % disinfectant solution, but not in 0.5 %. Publication in The Lancet (Reiss et al. 2000, 356, 310) Claim of parents. Court decision 2004: Clinics made a mistake and has to pay: Injury award 250,000, Monthly disability pension 300, Additional monthly pension 500. Also pay for all costs in future, eg by restraint

12 Outbreak in neonatology, 2011 Cleaning and disinfection: Quaternery ammonium compound (Quat) Low concentratioin (comparable 0.25 % like in Giessen) Eco-Wipes Pseudomonas: In disinfectant solution in high concentration autumn 2011, again 2012 On ventilation machine, just cleaned Single-use cloths in buckets, ready to use Compatibility of cloths and disinfectant (VAH) Loss of efficacy with time and by drying out (VAH) Contamination of cloths standing out (VAH) Growing of gram(-) bacteria in bucket, biofilms (VAH) If Quats: chemothermical reprocessing of buckets (Bode) Manual reprocessing is enough if aldehydes or alcohol (Bode) No restriction re disinfectants (Merz) No restrictions, manual disinfection better (Schьlke)

13 Investigation committee of Bremische Bьrgerschaft (Bremen state parliament) - Recommendation Not enough training of staff, Eg doctors: 22 planned, only 12 given. Not enough staff with special qualification in neonatology. Relation for nurses of 1 : 2 not fullfilled in most shifts. Sometimes one nurse had to care for 6 babies. Investigation committee of Bremische Bьrgerschaft (Bremen state parliament) - Recommendation Also before the outbreak, there were hints to deficits in cleaning. But they were not recognized as it should have been done. In highly sensitive areas, there should be permanently assigned cleaning staff. Staff number must be enough for maximum number of babies. Recommendations of RKI are mandatory, eg regarding relation of staff and babies Investigation committee of Bremische Bьrgerschaft (Bremen state parliament) - Recommendation Outbreak management showed many deficits. Outbreak was detected too late because of missing documentation of bacteria found. Routine screening should have started earlier. Thank you for your attention! Report to state authorities was too late. No outbreak management team only a group caring how to present in public and media. Link doctor did not have enough time for his job. Not enough hygiene nurses according to RKI recommendations