2304. Decreased Incidence of Methicillin-Susceptible Staphylococcus aureus (MSSA) Infections after Implementation of Routine Surveillance and Decolonization in a Level IV Neonatal Intensive Care Unit (NICU)

BACKGROUND: Staphylococcus aureus (SA) is a leading cause of hospital-acquired infection, including bloodstream infection (BSI), in NICUs. In this study, we evaluated the effect of screening and decolonization of MSSA-colonized babies with mupirocin on the rate of MSSA infection. Patients and Methods. Study design: Sequential time series. Pre-intervention period, January 2015–March 2017; wash out period, April 2017; intervention period, May 2017–March 2018. Population: Neonates admitted to a Level IV NICU with anticipated stay of greater than 2 days. Intervention: A single swab of the nares, umbilicus & groin was sent weekly for SA surveillance culture. MSSA-colonized neonates were decolonized with mupirocin application to nares, umbilicus and abraded skin twice daily for 5 days. Outcome measures: Comparison of rates of MSSA infections during pre- and post-intervention periods. Infections included BSI and skin/wound infections, excluding patients with MSSA from only eye or respiratory specimens. Comparators: Change in rates of Gram-negative and MRSA BSI. Change in rates of MSSA BSI in an affiliated NICU with the same medical staff but no intervention. RESULTS: MSSA BSI decreased from 0.37 per 1,000 hospital days (n = 15) to 0.00 (n = 0), P = 0.0092. All MSSA infections decreased from 0.62 (n = 25) to 0.11 (n = 2), P = 0.0078. Of 694 eligible neonates, 98.8% were screened at least once for MSSA colonization, which was detected in 92 (13.4%) infants. Median weekly prevalence of colonization was 6.7%. Median length of stay of neonates after initial detection of colonization was 30 days. Of colonized neonates, 92% received mupirocin treatment, with a median of 1 course of mupirocin treatment per patient (range, 1–7 courses). Of 54 isolates tested, all were mupirocin-susceptible. In contrast, there was no significant change in the rates of either MRSA (P = 0.71) or Gram-negative (P = 0.45) BSIs. In the comparison NICU, there was no significant change in rate of MSSA BSIs (P = 0.34). CONCLUSION: Despite a substantial burden of MSSA-colonized neonates, the intervention was associated with elimination of MSSA BSI and an 82% reduction in rate of MSSA infections. A potential confounding factor was the occurrence of a cluster of mupirocin-resistant MRSA during the intervention period with the associated intensified infection prevention measures. DISCLOSURES: All authors: No reported disclosures.