Nosocomial influenza infection as a cause of intercurrent fevers in infants.

All patients on an infants' ward manifesting intercurrent fevers were studied for viral and bacterial etiology during a community outbreak of influenza A. During a one-month period, of 29 infants admitted to the ward, 17 were hospitalized for seven or more days. Intercurrent fever complicated the course of 13 (76%) of these 17 infants. Nosocomially acquired influenza A infection was found in 13 infants. Two of these also contracted a dual infection with influenza B. The fever lasted an average of 2.7 days with a peak of 38.2 to 39.8 C. Initial white blood cell counts tended to by high and shifted to the left. These infants appeared to be at high risk for developing lower respiratory tract disease. Seven of the 12 had infiltrates on chest X-ray, and five subsequently developed a secondary bacterial pneumonia. These infants tended to be young, five were under 6 months, and all but one had underlying cardiorespiratory disease. They also appeared to have prolonge shedding of influenza virus from their nasal secretions. Six of seven shed the virus for 7 or 21 days.