title: Three consecutive outbreaks of Serratia marcescens in a neonatal intensive care unit.
abstract: We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of the University Hospital of Zurich. S. marcescens infection was detected in 4 children transferred from the NICU to the University Children's Hospital (Zurich). All isolates showed identical banding patterns by pulsed-field gel electrophoresis (PFGE). In a prevalence survey, 11 of 20 neonates were found to be colonized. S. marcescens was isolated from bottles of liquid theophylline. Despite replacement of these bottles, S. marcescens colonization was detected in additional patients. Prospective collection of stool and gastric aspirate specimens revealed that colonization occurred in some babies within 24 hours after delivery. These isolates showed a different genotype. Cultures of milk from used milk bottles yielded S. marcescens. These isolates showed a third genotype. The method of reprocessing bottles was changed to thermal disinfection. In follow-up prevalence studies, 0 of 29 neonates were found to be colonized by S. marcescens. In summary, 3 consecutive outbreaks caused by 3 genetically unrelated clones of S. marcescens could be documented. Contaminated milk could be identified as the source of at least the third outbreak.
authors.affiliation: Division of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, CH-8091 Zurich, Switzerland.
authors.forename: Felix
authors.initials: F
authors.lastname: Fleisch
authors.forename: Urs
authors.initials: U
authors.lastname: Zimmermann-Baer
authors.forename: Reinhard
authors.initials: R
authors.lastname: Zbinden
authors.forename: Gian
authors.initials: G
authors.lastname: Bischoff
authors.forename: Romaine
authors.initials: R
authors.lastname: Arlettaz
authors.forename: Katharina
authors.initials: K
authors.lastname: Waldvogel
authors.forename: David
authors.initials: D
authors.lastname: Nadal
authors.forename: Christian
authors.initials: C
authors.lastname: Ruef
mesh_terms: D000818:Animals; D003428:Cross Infection / Q000453:epidemiology*; D004196:Disease Outbreaks; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008892:Milk / Q000382:microbiology; D015995:Prevalence; D011446:Prospective Studies; D016868:Serratia Infections / Q000453:epidemiology*; D012706:Serratia marcescens; D013557:Switzerland / Q000453:epidemiology; D013806:Theophylline
chemical_list: D013806:Theophylline