Chickenpox outbreak among the staff of a large, urban adult hospital: costs of monitoring and control.

Chickenpox is a highly infectious disease of childhood, but there are increasing reports of occurrence in adults. A recent community epidemic of chickenpox resulted in 20 documented cases of adult chickenpox in a large metropolitan hospital. Nine of these cases resulted from direct exposure to an index patient and four were in tertiary contacts of the three index patients associated with the nosocomial outbreak. A total of 165.6 person-days of work were lost (estimated $18,000 cost) as a result of this outbreak, and 70 infection control unit person-hours were required during the investigation and control. This article reports a nosocomial epidemic and reviews guidelines for identification and control of adult chickenpox in a large hospital complex.