Detection of hantaviral antibodies among patients with hepatitis of unknown etiology in Japan

Hantaviral antibodies were detected in the sera from patients with hepatic disease of unknown etiology in Japan by several different serological diagn ostic methods. A total of 105 sera from diseased patients which were negati ve to A-G hepatitis virus infections in the Tokyo area were tested. Among t hem, 3 out of 73 sera from patients with chronic hepatic disease were posit ive to hantaviral antibody by enzyme-linked immunosorbent assay (ELISA), in direct immunofluorescent antibody assay (IFA) and Western blot analysis (WB ), Neutralizing antibody titers of the 3 sera to Seoul virus (SEO) were 4 t o 8 times higher than those to Hantaan virus (HTN), However, all of the 32 sera from patients with acute hepatitis were negative for hantaviral antibo dy, Among the 60 patients with chronic hepatitis in Hokkaido which were ser ologically negative to B and C hepatitis virus infection, one was positive for hantaviral antibody by ELISA and WE. In contrast, the sera from healthy adults in Japan, 550 from the Honshu and Kyushu regions, and 1,000 from th e Hokkaido region, were negative for hantavirus antibody. These results sho w that hantaviral antibodies are more frequently detected in patients with hepatic disease than in healthy adults. However, the observation that no po sitive sera were detected from patients with acute hepatitis implies that h antavirus might not be directly related to hepatitis.