Risk of infection with hepatitis A, B or C, cytomegalovirus, varicella or measles among child care providers

Background. Employment as a child care provider has been suggested as an indication for hepatitis A virus (HAV) immunization ; however, whether this occupational group is at increased risk of HAV infection is not well-defined. Methods. We obtained sera samples for testing for antibodies to hepatitis A, B and C, cytomegalovirus, varicella and measles from a sample of child care providers in King County, WA, and administered a questionnaire to assess employment characteristics and other potential risk factors for infection. We also compared the anti-HAV seroprevalence among providers with that of subjects in the Third National Health and Nutrition Survey, representative of the US general population. Results. Thirteen percent (48 of 360) of providers were anti-HAV-positive (46% (22 of 47) of foreign born vs. 8% (26 of 313) of US-born (P < 0.001)). In multivariate analysis anti-HAV seropositivity was associated with foreign birth, age, income and Hispanic ethnicity but was not associated with characteristics of employment. Seroprevalence among US-born providers tended to be lower than that among Third National Health and Nutrition Survey subjects of similar age, sex, race and income. Sixty-two percent of providers were seropositive to cytomegalovirus, which was associated with nonwhite race, changing diapers ≥3 days/week while at work and having a child in the household. Antibody prevalence was 1.4% to hepatitis B core antigen, 0.6% to hepatitis C, 94% to measles and 98% to varicella. Conclusions. The anti-HAV prevalence among US-born providers was low, and seropositivity was not associated with employment characteristics, indicating that occupational exposure to HAV is uncommon under non-outbreak circumstances.