Consumption of uncooked deer meat as a risk factor for hepatitis E virus infection: an age- and sex-matched case-control study.

It was reported previously food-borne transmission of hepatitis E virus (HEV) to humans from deer meat. The present study attempted to clarify whether eating uncooked deer meat is a major epidemiological risk factor for HEV infection in Kasai, a city in western Japan. In total, 45 volunteer subjects with experience of eating raw deer meat were enrolled. An equivalent number of people from the same area who had never eaten raw deer meat served as controls. The subjects and controls had comparable age and sex distributions. Serum anti-HEV IgG and anti-hepatitis A virus (HAV) IgG levels were measured in all 90 volunteers. There was no significant difference in age, overseas travel history, or rate of anti-HAV antibody positivity between the subjects and controls. Eight (17.7%) of the subjects but only one (2.2%) of the controls had measurable serum anti-HEV IgG levels (P = 0.014). Anti-HAV prevalence did not differ between the anti-HEV-positive and negative groups. The results suggest that eating uncooked deer meat is an epidemiological risk factor for HEV infection in the studied area. In countries such as Japan where deer meat is sometimes eaten raw, attention must be paid to this route of HEV infection.