Nosocomial respiratory syncytial virus infections in an intensive care nursery: rapid diagnosis by direct immunofluorescence.

A nosocomial outbreak of respiratory syncytial virus infections involved 8 of 17 infants in an Intensive Care Nursery and one additional infant in the adjoining Newborn Nursery. Immunofluorescent staining of nasopharyngeal specimens was positive in six of seven virologically confirmed cases (86%). One additional case with negative viral cultures was also identified by this technique. Viral isolation in tissue cultures required an average of 4.9 days, whereas results of immunofluorescent studies were available in two to four hours. Rapid identification of infected infants by immunofluorescence permitted prompt institution of infection control measures.