A total of 10 Japanese patients with acute sporadic hepatitis E in Tokyo and Kanagawa area from 1998 to 2004 were analyzed for epidemiological and viro-genetic characteristics of their HEV infections. Our findings therefrom corroborated the previous ones on the middle-aged male predominance. Noteworthy was that all were alcohol drinkers except for one female patient. Two of the drinkers had a fondness for eating uncooked or undercooked pork meat or liver. The one and only non-drinker among the subjects was engaged in the job of building-sanitation. Molecular analyses indicated that most of the HEV isolates from these patients segregated to a cluster within genotype III, suggesting these strains (if not all) might be autochthonous in the Tokyo and Kanagawa area.
