Serratia Infection Epidemiology Among Very Preterm Infants in the Neonatal Intensive Care Unit

Abstract

Background: Serratia spp. are opportunistic, multidrug resistant, Gram-negative pathogens, previously described among preterm infants in case reports or outbreaks of infection. We describe Serratia late-onset infection (LOI) in very preterm infants in a large, contemporary, nationally representative cohort. Methods: In this secondary analysis of prospectively collected data of preterm infants born 401–1500 grams and/or 22–29 weeks gestational age from 2018 to 2020 at 774 Vermont Oxford Network members, LOI was defined as culture-confirmed blood and/or cerebrospinal fluid infection > 3 days after birth. The primary outcome was incidence of Serratia LOI. Secondary outcomes compared rates of survival and discharge morbidities between infants with Serratia and non-Serratia LOI. Results: Among 119,565 infants, LOI occurred in 10,687 (8.9%). Serratia was isolated in 279 cases (2.6% of all LOI; 2.3 Serratia infections per 1000 infants). Of 774 hospitals, 161 (21%) reported at least one Serratia LOI; 170 of 271 (63%) cases occurred at hospitals reporting 1 or 2 Serratia infections, and 53 of 271 (20%) occurred at hospitals reporting ≥5 Serratia infections. Serratia LOI was associated with a lower rate of survival to discharge compared with those with non-Serratia LOI (adjusted relative risk 0.88, 95% CI: 0.82–0.95). Among survivors, infants with Serratia LOI had higher rates of tracheostomy, gastrostomy and home oxygen use compared with those with non-Serratia LOI. Conclusions: The incidence of Serratia LOI was 2.3 infections per 1000 very preterm infants in this cohort. Lower survival and significant morbidity among Serratia LOI survivors highlight the need for recognition and targeted prevention strategies for this opportunistic nosocomial infection.

Outbreak of Serratia marcescens in the Neonatal Intensive Care Unit of a Tertiary Care Hospital in Mexico

“…According to Canadian studies, the incidence of Serratia infections is estimated at 10.8 per 100,000 persons per year, with a hospital incidence rate of 0.4 per 1,000 hospitalized patients [ 13 ]. On the other hand, a multicenter study of premature infants in 774 hospitals in the United States showed an increased incidence of invasive Serratia, corresponding to approximately 2.3 Serratia infections per 1,000 premature infants [ 29 ]. Both studies showed a higher incidence than that found in our work.…”

Neonatal Brain Abscess with Serratia marcescens after Intrauterine Infection: A Case Report

“…There have been outbreaks of Serratia marcescens in neonatal intensive care units described in the literature [ 2 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 23 ]. Still, they often did not progress to the central nervous system or other complications.…”

“…Environmental sources have been described (e.g., contaminated medical devices, parenteral nutrition, contaminated milk, intravenous and topical solutions, liquid soap, respiratory care equipment, and air conditioning) [ 6 , 7 , 8 , 9 ]. Serratia can cause invasive systemic infections in newborns due to the immaturity of the immune system [ 10 , 11 , 12 ].…”

Serratia marcescens Colonization in a Neonatal Intensive Care Unit Has Multiple Sources, with Sink Drains as a Major Reservoir

“…Serratia marcescens is the most important opportunistic human pathogen among Serratia species, often multidrug resistant and involved in outbreaks of HAIs in neonatal intensive care units (NICU) (24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34). A recent study reported an incidence of 2.3 Serratia late-onset infections per 1,000 very preterm infants, associated with lower survival and significant morbidity (35). S. marcescens is the second most frequently cited species in studies linking sinks with bacterial HAI in NICU, preceded by Pseudomonas aeruginosa (20).…”