SERRATIA-MARCESCENS INFECTIONS IN NEONATAL DEPARTMENTS - DESCRIPTION OF AN OUTBREAK AND REVIEW OF THE LITERATURE

An outbreak of colonization and infection with Serratia marcescens occ urred in a neonatal intensive care unit (NICU). S. marcescens was isol ated from five preterm infants (gestational age 25-30 weeks). Two infa nts developed septicaemia, which were both fatal, and one infant (the presumed index case) had conjunctivitis due to S. marcescens. Two infa nts were colonized without clinical signs of infection. All infants we re treated with antibiotic regimens including ciprofloxacin and gentam icin. The DNA fingerprints of isolates were determined by enterobacter ial repetitive intergenic consensus primers by the polymerase chain re action. This showed that a single strain had spread in the NICU. An ex tensive investigation pointed to an infant born from a mother with an intra-uterine infection after prolonged rupture of foetal membranes as a presumed source of the outbreak. A reservoir, other than the infect ed or colonized infants and their immediate vicinity, was not found, w ith the sole exception of the waste jar of a Na+/K+-analysis apparatus . Containment of the outbreak was achieved by closure of the NICU for new admissions, strict hygienic measures and cohort nursing of the inf ected and colonized infants. It was considered especially important to handle the infants with gloves, since frequent hand carriage of staff with S. marcescens was found when gloves were not used.