Survey of neonatal unit outbreaks in North London: identifying causes and risk factors

This survey was undertaken after a number of neonatal unit (NNU) outbreaks were reported to the North London health protection teams (HPTs).

To determine the diversity of the outbreaks, ascertain potential sources and contributing factors, and identify the investigative procedures followed and control measures implemented.

Using a structured questionnaire, information from the HPT database was collected for all NNU outbreaks reported between January 2010 and February 2011.

Ten outbreaks were identified from seven hospitals in 14 months. There was one para-influenza outbreak, seven Staphylococcus aureus [including six meticillin-resistant S. aureus (MRSA)] outbreaks, and two Gram-negative outbreaks. Potential sources of transmission identified for the MRSA outbreaks were healthcare worker (HCW)-assisted transmission (N = 2) and mother-to-baby transmission with onward HCW-assisted transmission (N = 3). An environmental source with onward HCW-assisted transmission was documented for one of the Gram-negative outbreaks. Interventions included patient screening and enhanced cleaning (N = 10), isolating/cohorting affected neonates (N = 9), barrier nursing (N = 6), staff movement restrictions (N = 5), hand hygiene audits (N = 4), staff screening (N = 4), household contact screening (N = 3) and environmental sampling (N = 3). Potential contributing factors included inadequate staffing levels, cluttered unit, inadequate sterilization of communal milk-expressing equipment and inappropriate follow-up of MRSA results.

This survey determined the diversity of NNU outbreaks in North London, and highlighted the importance of a multi-faceted approach to outbreak control. These data will assist in the development of clinical standards for the prevention, control and reporting of NNU outbreaks, and guidance for best practice in NNUs.