| Abstract: | It is estimated that approximately 70 to 80% of the world's HBsAg carriers live in Southeast Asia, but studies of delta infection in this area are still limited. We studied 323 HBsAg seropositive patients in Japan, and 4 (1.2%) of them were found to be positive for anti-delta antibody, with none positive for delta antigen. These four patients did not belong to the known high-risk groups for delta infection. One HBeAg positive female gave birth to a baby girl, and perinatal transmission of hepatitis B virus and delta was successfully blocked by a combination of hepatitis B immunoglobulin and vaccine. This study in the Tokyo-Chiba area showed delta infection, though low in frequency, among ordinary Japanese citizens. It has been reported that delta antigen is highly infectious to HBsAg carriers and that its infection will cause severe liver damage. Once introduced, it could become epidemic among non-drug users in a country where hepatitis B virus infection is endemic. At this moment, the only way of preventing such a disaster appears to be to reduce the number of chronic carriers by interruption of vertical transmission. |
