Occupational risk of hepatitis B from institutionalized mentally retarded HBsAg carriers: a prospective study.

In an institution for the mentally retarded, a total of 13 (2.4%) susceptible employees seroconverted for hepatitis B during 539 person-years. Two of them developed acute hepatitis B; the cost of their medical care and temporary disability was $7,772. Eleven seroconverters had no elevation of serum alanine aminotransferase, and all seroconverters recovered without chronic sequelae. Nine converters acquired antibody to HBsAg alone; three of these had no client contact. Difficulty in identifying nonoccupational causes of hepatitis B infection in the institutional setting often leads to labeling of all seroconversions as occupationally acquired. Hepatitis B vaccine is recommended for client-care personnel.