Soroprevalência para hepatite A e hepatite B em quatro centros no Brasil Hepatitis A and hepatitis B seroprevalence in four centers in Brazil

Avaliou-se a prevalência de anticorpos para as hepatites A e B em 3.653 indivíduos, em quatro regiões brasileiras. As prevalências de anti-VHA e de anti-HBc foram 64,7% e 7,9%, respectivamente. Prevalências mais elevadas de anti-VHA (92,8%) e de anti-HBc (21,4%) foram observadas na região Norte. Em outras regiões, prevalências de anti-VHA acima de 90% foram alcançadas apenas em idades mais avançadas, indicando uma endemicidade intermediária e prevalência significativamente mais elevada foi observada no grupo de baixo nível sócio-econômico, entre 1 e 30 anos. Para o anti-HBc observou-se um aumento na prevalência entre adolescentes e uma prevalência significativamente mais elevada no grupo de baixo nível sócio-econômico, entre 1 e 20 anos. Prevalência de 3,1% foi encontrada em crianças de 1 ano, sugerindo a transmissão vertical. Os principais resultados deste estudo, indicam que pré-adolescente/adolescentes de algumas cidades brasileiras estão em risco para as hepatites A e B, mas por diferentes motivos.<br>The prevalence of antibodies to hepatitis A and B virus was assessed in 3,653 subjects across four regions of Brazil. The anti-HAV and anti-HBc seroprevalence were 64.7% and 7.9%, respectively. The highest anti-HAV (92.8%) and anti-HBc (21.4%) rates were seen in the Northern region. In other regions, anti-HAV seroprevalence over 90% was only reached in the more elderly, indicating an intermediate endemicity and a significantly higher anti-HAV prevalence was seen in the low socioeconomic group between 1-30 years. With respect to anti-HBc seroprevalence an increase was seen in adolescents and there was a significantly higher anti-HBc prevalence in the lower socioeconomic group between 1-20 years. A 3.1% anti-HBc prevalence was seen in one-year-old infants, suggesting a vertical transmission. The major findings of this study indicate that the pre-adolescent and adolescent population in some Brazilian cities are at greatest risk from both hepatitis A and B infection, but for different reasons

Hepatitis B seroprevalence in Latin America

The seroprevalence of hepatitis B was investigated in over 12 000 subjects in six countries of Latin America: Argentina, Brazil, Chile, the Dominican Republic, Mexico, and Venezuela. Each study population was stratified according to age, gender, and socioeconomic status. Antibodies against hepatitis B core antigen (anti-HBc) were measured in order to determine hepatitis B infection. The highest overall seroprevalence was found in the Dominican Republic (21.4%), followed by Brazil (7.9%), Venezuela (3.2%), Argentina (2.1%), Mexico (1.4%), and Chile (0.6%). In all the countries an increase in seroprevalence was found among persons 16 years old and older, suggesting sexual transmission as the major route of infection. In addition, comparatively high seroprevalence levels were seen at an early age in the Dominican Republic and Brazil, implicating a vertical route of transmission