title: The epidemiology of hepatitis B antigen and antibody among Panamanian Cuna Indians.
abstract: Previous studies of hepatitis B antigen (HBsAg) and antibody to it (anti-HBs) showed widely differing exposures between Panamanian Indian tribes. Cuna Indians living on islands appeared infrequently exposed to HBsAg; we found no one antigenemic and low age specific anti-HBs rates. In contrast, mainland dwelling Guaymi and Chocó Indians had a high prevalence of anti-HBs. We have now measured HBsAg by counterelectrophoresis and anti-HBs by radioimmunoassay in two Cuna Indian groups who live in the Darien forest. The prevalence of HBsAg among Darien Cuna was low, 3 positive of 239 tested, but 106 (44%) had anti-HBs. Darien Cuna thus evidenced greater exposure to HBsAg than island Cuna (8% had anti-HBs) and had an anti-HBs prevalence similar to the neighboring Chocó Indians (42%). The Guaymi Indians of western Panama had a lower frequency of anti-HBs (29%) than either Chocó or mainland Cuna but their frequency of chronic antigenemia was significantly greater. These data suggest that while exposure may be a function of village habitat, chronic antigenemia may reflect differences in host responses.
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000914:Antibodies, Viral / Q000302:isolation & purification*; D002648:Child; D002675:Child, Preschool; D006168:Guinea Pigs; D006509:Hepatitis B / Q000453:epidemiology; D006511:Hepatitis B Antigens / Q000302:isolation & purification*; D006515:Hepatitis B virus / Q000302:isolation & purification; D006801:Humans; D007199:Indians, South American; D007223:Infant; D008297:Male; D010176:Panama; D012931:Social Environment
chemical_list: D000914:Antibodies, Viral; D006511:Hepatitis B Antigens