Prevalence of delta agent among Chinese in Taiwan and Los Angeles.

The prevalence of delta agent among 120 Chinese patients with HBsAg-positive chronic active and hepatocellular carcinoma from Taiwan and Los Angeles were studied by serological assay for antibody to delta antigen and immunoperoxidase staining for delta antigen in the liver biopsies. Of 120 patients, only four with chronic active hepatitis and one with hepatocellular carcinoma from Taiwan had antibody to delta antigen in their sera, while none was detected in the patients from Los Angeles. Indirect immunoperoxidase staining for delta antigen in the liver tissue from three of the patients with circulating anti-delta was positive. Thus, the overall prevalence of delta infection was 5.8% among the 86 patients from Taiwan, and 0% in the 34 Chinese patients from Los Angeles.