Acute Hepatitis Associated With Autochthonous Hepatitis E Virus

Locally acquired hepatitis E infection is increasingly being observed in industrialized countries. We report 2 cases of au-tochthonous acute hepatitis E in the United States. Hepatitis E virus genotype 3a related to US-2 and swine hepatitis E virus strains was isolated from one of the patients, indicating po-tential food-borne or zoonotic transmission. Hepatitis E virus (HEV) infection is a major cause of acute viral hepatitis worldwide. In developing countries, it presents as both epidemic and sporadic hepatitis that is mainly associated with fecally contaminated drinking water [1]. Traditionally, HEV infections in industrialized countries have been associated with travel to regions of endemicity; however, recently, locally ac-quired cases of HEV infection are increasingly being observed in Europe and Japan [2, 3]. The specific sources of these au-tochthonous infections remain largely unknown. In the United States, 5 cases of autochthonous acute hepatitis E have been reported to date [4–7], but no clear source of infection was identified despite extensive investigation. In September 2009, 2 unrelated patients with no recent travel history presented with signs and symptoms of acute hepatitis to the same hospital in San Antonio, Texas. Both patients had serologic evidence of HEV infection. We describe the clinical presentation of the patients and the investigation to determine the source of infection