Occupationally related outbreak of chickenpox in an intensive care unit.

OBJECTIVE To report occupationally related outbreak of chickenpox in intensive care unit (ICU). CASE PRESENTATION AND INTERVENTION The index patient was a 4-year-old child who presented with a 3-day history of fever and rash and was clinically diagnosed as chickenpox encephalitis. She was admitted to an isolation room in ICU, kept on oxygen mask and given intravenous fluids, anticonvulsant, antipyretic and acyclovir. Twelve hours later, the patient was transferred to Infectious Diseases Hospital. Secondary cases were three unvaccinated ICU staff nurses who developed chickenpox 16-21 days following exposure. They were also transferred to Infectious Diseases Hospital. The affected nurses were interviewed and filled out a questionnaire. Individual immune status was verified by reviewing previous varicella zoster-IgG screening data for all ICU staff. The chickenpox case was defined according to the CDC case classification. All were treated with no complications. CONCLUSION This report shows that adherence to isolation precautions, exclusion of susceptible staff from attending the affected patient, education, pre-employment anti-VZV-IgG screening and vaccine coverage of staff could have prevented the occurrence of this outbreak.