Seroreactivity to hepatitis E virus in areas where the disease is not endemic

If the occurrence of hepatitis E virus antibody (anti-HEV) in regions where the disease is not endemic represents infection, rates may be greater in high-risk populations and behavioral correlates may reflect recognized transmission modes. Serum samples from 300 homosexual males, 300 injection drug users (IDUs), and 300 blood donors from Baltimore, Md., were tested for anti-HEV by enzyme immunoassay. Anti-HEV was found in an unexpectedly high percentage of homosexual men (15.9%) and IDUs (23.0%). However, anti-HEV was present in a similar proportion of blood donors (21.3%) (P > 0.05), while hepatitis A, B, and C virus antibodies were more prevalent in the high-risk groups (P < 0.001). Among homosexual men, anti-HEV was not significantly correlated with a history of hepatitis, high-risk sexual practices, or sexually transmitted infections, in contrast to hepatitis A and B antibodies. Among IDUs, anti-HEV was not significantly associated with a history of hepatitis or high-risk drug-using practices, as was found with hepatitis C antibodies. In a setting without endemic hepatitis E disease, there was no evidence that anti-HEV reflected subclinical infection. Until the basis for HEV seroreactivity in such areas is elucidated, anti-HEV results should be interpreted with caution.