Seroepidemiology of hepatitis A antibodies among children's hospital staff

Background. With improved socioeconomic conditions, adults are more frequently seronegative for hepatitis A virus (HAV) and therefore susceptible to infection. A safe and efficacious active HAV vaccine has been developed and licensed. The general recommendation is to vaccinate populations at increased occupational exposure to HAV. Aim. To determine the seroprevalence of HAV antibodies among children's hospital employees and to correlate seropositivity with demographic and occupational variables as a basis for formulating vaccine recommendations. Methods. The staff of a tertiary pediatric medical center participated by answering a structured questionnaire on demographic and occupational data and by donating venous blood for determining HAV antibodies by an enzyme immunoassay. Univariate and multivariate analyses were conducted to identify variables associated with HAV seropositivity. Results. HAV antibodies were found in 48.3% of the 499 employees studied, being lowest in pediatricians (38.7%), and increased with years of work at the hospital, job percentage and contact with pediatric patients. However, multivariate analysis showed that only the sociodemographic variables (age and crowding during childhood) were independently and significantly associated with seropositivity. Conclusions. HAV seropositivity was associated mainly with sociodemographic variables. Most children's hospital employees, especially pediatricians and other young (<40 years) employees, are seronegative and therefore susceptible to HAV. Vaccination of the high risk groups should be considered.