Two 71-year-old males (Case 1 and 2) with liver dysfunction were admitted to our hospital and diagnosed with acute hepatitis E due to detection of hepatitis E virus (HEV) RNA or IgM class anti-HEV in their sera. Since they ate the same rare wild boar meat at the same ritual, the boar meat was considered to be the infection source. Phylogenetic analysis showed that HEV strain identified in Case 1 segregated to a cluster of "Aichi/Shizuoka Strains". It seems that the "Aichi/Shizuoka Strain", an atypical genotype 4 strain compared to those found in other part of Japan, is prevailing within this small geographic area.
