Antigenic subgroups of hepatitis B (surface) antigen in Berlin (West) and their epidemiological aspects.

Sera of 334 hepatitis B patients and 118 sera of HBsAg carriers were tested for the distribution of the subgroups ad and ay by means of rheophoresis technique or solid phase radiommunoassay. The distribution of subgroups revealed a typical pattern. The ad-antigen determinant was more frequent in hepatitis B patients, blood donors and hemodialysis patients whereas the ay determinant was detected in drug users, guest workers and juveniles at a considerably higher percentage. The difference in distribution is discussed as an epidemiological phenomenon of hepatitis B virus, dependent on environmental factors characteristic for certain groups of the population. The routine testing for HGsAg subgroups is recommended as a valuable epidemiologic tool.