BORSA carriage among health care workers at NICU and pediatric ward.

Abstract Background During a MRSA contact tracing and screening investigation, we encountered two Borderline Oxacillin-Resistant Staphylococcus aureus (BORSA) positive screening cultures among Neonatal Intensive Care Unit (NICU) health care workers (HCW).This finding led to further investigations. Materials/methods An infection control team was initiated after the discovery. The team initiated additional infection control measures and evaluated new findings. All NICU and paediatric ward HCW were screened for BORSA carriage, and a prospective BORSA 7 week monitoring period for patients was observed. To assess the likelihood of an outbreak with direct transmission among HCW, the BORSA isolates were analyzed using AFLP and whole-genome sequencing (WGS). Results Positive HCW were prohibited from clinical work while awaiting the results from the screening program. 127 NICU and 77 general pediatric ward HCW were screened for BORSA carriage, 5 HCW were BORSA positive. 72 patients were screened during the 7 week period yielding a total of 138 cultures, ranging from 1 to 9 cultures per patient. No spread from HCW to patients occurred, and the BORSA screening programme was discontinued. WGS analysis with core genome MLST of all 5 BORSA strains showed relatedness between two NICU strains. Conclusions During a 7 week period, no transmission of BORSA positive HCW to neonates were observed in either screening or clinical cultures. More vigilance and experience is needed to design adequate evidence-based interventions in the future for this vulnerable population.