AMA Council on Scientific Affairs. Immunization of health care workers with varicella vaccine.

Varicella-zoster virus (VZV) is the etiologic agent of two common diseases: varicella (chickenpox) and herpes zoster (shingles). Groups such as infants under one year of age, the immunocompromised, and adults are at increased risk of developing complications from VZV infection. The transmission of VZV within health care facilities from contact with infected patients, staff, and visitors is a potentially serious problem. Nosocomial outbreaks of varicella can result in significant morbidity and mortality in high-risk patients, particularly in pediatric wards. VZV transmission to susceptible individuals is difficult to prevent because exposures may occur before appropriate infection control procedures can be implemented. In 1995, a varicella vaccine was approved for use in the United States. The vaccine has been shown to be fairly effective in preventing varicella in adults and very effective in preventing severe disease. While current data indicate that the vaccine is safe and poses minimal risks, more research is needed to address concerns about the long-term safety, efficacy, and epidemiological impact of more widespread use of the vaccine. It is important for health care workers, especially those working with high-risk groups, to know their VZV immune status. Unless contraindicated, health care workers who have no history of VZV infection and are serologically negative should be considered a priority for immunization with the varicella vaccine. Administration of the vaccine to health care workers could reduce nosocomial transmission of VZV. Furthermore, significant cost and labor savings could be realized by avoiding expensive and potentially disruptive infection control measures.