Nosocomial pertussis infection of infants: still a risk in 2009.

The Sydney West Centre for Population Health investigated a confirmed pertussis infection in a health care worker on a maternity ward and identified pertussis infection in 4 neonates cared for by this case. This report describes the public health intervention to identify and prevent further cases. Of the 4 neonates, three were laboratory-confirmed cases and one was diagnosed on clinical grounds alone. All were cared for by the infected worker during only one shift and developed symptoms six to 16 days afterwards. No other possible source of infection was identified. This investigation highlights the need to maintain awareness, particularly amongst staff working with neonates, that pertussis infection can arise despite complete vaccination. Thus it is important to investigate new coughing illnesses and exclude symptomatic staff from contact with neonates until pertussis infection is excluded or effectively treated. The burden on the health system arising from a pertussis infection in a health care worker in a high-risk setting is also described with the hospitalisation of 4 infants, and prophylactic antibiotics given to 73 new mothers, infants and health care workers.