title: Consecutive Serratia marcescens multiclone outbreaks in a neonatal intensive care unit.
abstract: BACKGROUND
  This report describes 3 consecutive outbreaks caused by genetically unrelated Serratia marcescens clones that occurred in a neonatal intensive care unit (NICU) over a 35-month period.
  
  
  METHODS
  Carriage testing in neonates and health care workers and environmental investigation were performed. An unmatched case-control study was conducted to identify risk factors for S marcescens isolation.
  
  
  RESULTS
  During the 35-month period, there were 57 neonates with S marcescens isolation in the NICU, including 37 carriers and 20 infected neonates. The prevalence rate of S marcescens isolation was 12.3% in outbreak 1, 47.4% in outbreak 2, and 42% in outbreak 3. Nine of the 20 infected neonates died (45% case fatality rate). A total of 10 pulsed field gel electrophoresis types were introduced in the NICU in various times; 4 of these types accounted for the 9 fatal cases. During outbreak 3, a type VIII S marcescens strain, the prevalent clinical clone during this period, was detected in the milk kitchen sink drain. Multiple logistic regression revealed that the only statistically significant factor for S marcencens isolation was the administration of total parenteral nutrition.
  
  
  CONCLUSIONS
  Total parenteral nutrition solution might constitute a possible route for the introduction of microorganisms in the NICU. Gaps in infection control should be identified and strict measures implemented to ensure patient safety.
authors.affiliation: Department for Interventions in Health Care Facilities, Hellenic Center for Disease Control and Prevention, Athens, Greece. helen-maltezou@ath.forthnet.gr
authors.forename: Helena C
authors.initials: HC
authors.lastname: Maltezou
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Tryfinopoulou
authors.forename: Panos
authors.initials: P
authors.lastname: Katerelos
authors.forename: Lemonia
authors.initials: L
authors.lastname: Ftika
authors.forename: Olga
authors.initials: O
authors.lastname: Pappa
authors.forename: Maria
authors.initials: M
authors.lastname: Tseroni
authors.forename: Evangelos
authors.initials: E
authors.lastname: Kostis
authors.forename: Christos
authors.initials: C
authors.lastname: Kostalos
authors.forename: Helen
authors.initials: H
authors.lastname: Prifti
authors.forename: Konstantina
authors.initials: K
authors.lastname: Tzanetou
authors.forename: Alkiviadis
authors.initials: A
authors.lastname: Vatopoulos
mesh_terms: D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology; D016022:Case-Control Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D004340:Drug Contamination; D004783:Environmental Microbiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008297:Male; D017720:Molecular Epidemiology; D058889:Molecular Typing; D057947:Parenteral Nutrition Solutions; D012307:Risk Factors; D016868:Serratia Infections / Q000453:epidemiology* / Q000382:microbiology; D012706:Serratia marcescens / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D057947:Parenteral Nutrition Solutions