Serratia marcescens outbreak in a neonatal intensive care unit associated with contaminated donor milk

Abstract

Objective: Investigation of the origin of a Serratia marcescens outbreak in a neonatal intensive care unit. Design: Retrospective case-control study. Setting: Regional level 3 perinatal center in Germany. Patients: This study included 4 S. marcescens-positive and 19 S. marcescens-negative neonates treated between February 1 and February 26, 2019, in the neonatal intensive care unit. Methods: A case-control study was performed to identify the source of the outbreak. The molecular investigation of S. marcescens isolates collected during the outbreak was performed using pulsed-field gel electrophoresis and next-generation sequencing. Results: The retrospective case-control study showed a significant correlation (P