RESUMO
Report presenting the results of a study made of Hepatitis B viral markers. A total of 7.487 donor blood samples from 13 Western Hemisphere countries (Argentina, Barbados, Brazil, Chile, Colombia, Costa Rica, the Dominican Republic, Ecuador, Mexico, Peru, Puerto Rico, Suriname, and Venezuela) were tested for various markers of hepatitis B virus (HBV) infection with several different techniques. HBsAg was detected in 1.6 per cent of the samples, anti-HBs in 20.2 per cent, and anti-HBs in 21.3 per cent. The incidence of HBsAg varied from 0.2 per cent (in Puerto Rican samples) to 4.1 per cent (in the samples from the Dominican Republic). Overall, 5.8 per cent of the samples found to contain HBsAg also contained HBeAg, while 24.8 per cent had detectable anti-HBe. Sixty-six (54.5 per cent) of the 121 HBsAg-positive samples were found to contain subtype HBsAg/ad, and 5(4.1 per cent) were found to contain subtype HBsAg/ay. Subtypes of the remaining samples could not be determined because of insufficient antigen. In a comparitive study, reverse passive hemagglutination (RPHA), counterelectrophoresis (CEP), and immunodiffusion (ID) detected by HBsAg in 90.9. 67.2, and 62.0 per cent of the samples previously found positive by radioimmunoassay (RIA) screening. Considerable variation was observed in the prevalence of HBV markers in samples from different countries, the highest prevalence being 82.8 per cent in samples from the Dominican Republic. Over-all, the findings suggest that exposure to HBV is quite extensive in some Latin American populations......(AU)
