RESUMO
We report the results of a study carried out to evaluate the extent of hepatitis A virus (HAV) and hepatitis B virus (HBV) circulation in Somalia. Serum samples were collected from 593 subjects (age range 0-83 years) and tested for anti-hepatitis A (HAV) and anti-HAV IgM. Serum samples taken from 1272 individuals (age range 0-83 years) were tested for HBsAg, anti-HBsAg, anti-HBcAg, HBeAg and anti-HBeAg. We confirmed a very high rate of HAV exposure (about 90% of the subjects tested had circulating anti-HAV) as is typical of fecal-orally transmitted infectious agents. The age-specific anti-HAV IgM prevalence suggests that HAV infection is acquired very early in life. Our data also indicate a high rate of HBsAg carriers (range: 10.5%-27.4%) in the Somalian population. When all markers are considered, 60% of the adult population showed evidence of HBV exposure. HBV spreads very subtly: in fact, it is generally transmitted via non-overtly percutaneous routes. In Somalia, hepatitis A virus infection is highly endemic and occurs very early in life. Hepatitis B virus infection is also widespread in this country.
Assuntos
Vírus da Hepatite B/imunologia , Hepatovirus/imunologia , Fatores Etários , Portador Sadio/epidemiologia , Portador Sadio/imunologia , Hepatite A/epidemiologia , Hepatite A/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite B/epidemiologia , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos da Hepatite B/sangue , Humanos , Imunoglobulina M/sangue , Prevalência , Estudos Soroepidemiológicos , Fatores Sexuais , Somália/epidemiologiaRESUMO
In developing countries, HAV seems to be responsible for a widespread, inapparent and protective infection during early childhood. This report emphasizes early infection and its relationship to protection by passive immunity from maternal antibody in a highly endemic area such as Somalia. Our result show that HAV infection in Somalia primarily occurs during the first 4 years of life (4 months to 4 years). Cases are infrequent in the first 3 months due to passive immunity secondary to maternal antibody (cord-blood and colostrum anti-HAV). As the level of protection declines, the rate of acute infection rises as determined by the presence of IgM-specific anti-HAV.
