Pathogenic bacteria rapidly colonize sinks of a neonatal intensive care unit: results of a prospective surveillance study

Background

Hospital sinks are known to harbour bacteria with the potential to infect patients.

Aim

To examine bacterial growth in the sinks of a newly constructed neonatal intensive care unit (NICU) during the transition from an established NICU within the same facility.

Methods

This was a prospective study of pathogenic bacterial growth in NICU handwashing sinks before and after the new NICU was occupied. Samples from various sink traps were cultured longitudinally, and comparison was made between the established NICU and the new NICU.

Findings

Potentially pathogenic bacteria colonized sinks rapidly in the new NICU within 1 month of occupation. During the study period, between 29^th June 2021 and 2^nd September 2022, 62 samples were collected from 11 sinks, of which 43 (69.4%) tested positive. The mean semi-quantitative bacterial growth score was notably higher in the sink in the milk preparation room compared with the sinks in the patient care area in the new NICU (40.67 vs 1.768; P=0.025). The bacterial profiles in the sink in the new NICU milk preparation room mirrored that of the established NICU, with a predominance of Klebsiella pneumoniae and Enterobacter cloacae complex. In handwashing sinks of both the established NICU and the new NICU, the dominant colonizing pathogen was Burkholderia cepacia complex, followed by Serratia marcescens and Elizabethkingia spp. Cessation of sink use reduced the bioburden of bacteria significantly in the NICU handwashing sink drains.

Conclusion

Handwashing sinks were colonized rapidly with pathogenic bacteria in a newly constructed NICU. More diversified and prolific growth of pathogenic bacteria was noted in the sink in the milk preparation room.