Intensified colonisation screening according to the recommendations of the German Commission for Hospital Hygiene and Infectious Diseases Prevention (KRINKO): identification and containment of a Serratia marcescens outbreak in the neonatal intensive care unit, Jena, Germany, 2013-2014.

Abstract

In 2013, the German Commission for Hospital Hygiene and Infectious Disease Prevention (KRINKO) stated that extending weekly colonisation screening from very low birth weight (VLBW) infants (<1500g) to all patients in the Neonatal Intensive Care Unit (NICU) might be useful. After implementing this recommendation, we detected a previously unnoticed cluster of Serratia marcescens. Strains were typed by Pulsed Field Gel Electrophoresis (PFGE). Over 6months, 19 out of 159 infants acquired S. marcescens. Twelve of the nineteen patients with S. marcescens were non-VLBW infants, and they were colonised significantly earlier than were VLBW infants (median 17 vs. 28days; p<0.01). Molecular typing revealed a polyclonal outbreak with multiple strain types leading to one or two transmissions each and a dominating outbreak strains being involved in an explosive outbreak involving eight neonates. The revised KRINKO recommendation may help identify unnoticed outbreaks. Colonised non-VLBW patients may be an underestimated source of S. marcescens.