Seroprevalence of hepatitis A in children and adolescents

To determine the seroprevalence of hepatitis A (HAV) in children and adolescents aged 1 to 14 years, and to identify factors associated with a history of infection.

This was a cross-sectional epidemiological study, conducted form February to August 2006 in the city of Curitiba, Paraná, Brazil, and the surrounding municipalities (Greater Curitiba). Laboratory analysis comprised qualitative assay for total HAV antibodies in whole blood samples.

A total of 901 children and adolescents were recruited for the study. Age distribution was as follows: 1 to 4 years, n = 237 (26.3%); 5 to 9 years, n = 313 (34.7%); and 10 to 14 years, n = 351 (39%). The global rate of seroprevalence was 19.8%, and seroprevalence rates by age group were 3%, 21.1% and 29.9% respectively (p < 0.01). Multivariate analysis demonstrated that the following factors, in combination, had a positive association with the prevalence rate of antibodies against HAV in the study population: age groups 5 to 9 and 10 to 14 years, living in a household with more than one inhabitant per room, shared eating area and low per capita income.

The results show a low prevalence of antibodies against HAV, which justifies the use of prophylactic measures, including early vaccination.