Outbreak of pertussis in a neonatal intensive care unit--Louisiana, 2004

BackgroundOn November 12, 2004, a 5-month-old infant, admitted in the neonatal intensive care unit (NICU) of a Louisiana regional hospital since birth, was diagnosed with pertussis. Measures to prevent further transmission, in the NICU and beyond, were immediately put into place.MethodsExposed contacts were identified among other patients of the NICU, health care workers, and family members. All were offered pertussis testing and prophylactic treatment.ResultsThe source of the outbreak was not identified. Despite the immediate implementation of control measures, a total of 37 additional NICU patients, 198 health care workers, and 15 family members were identified as potentially exposed contacts. Three more infants were diagnosed with pertussis, one of them after having been transferred to the NICU of another hospital in the state.ConclusionThe source of this outbreak was believed to be an adult, either a hospital worker or an outside visitor. The incident clearly illustrates the infection control challenges for hospital units serving newborns and young infants in an era of changing epidemiology of pertussis.