Public Health

Endemic hepatitis E not confined to tropics

Last Updated: 2008-12-31 12:26:58 -0400 (Reuters Health)

By Will Boggs, MD

NEW YORK (Reuters Health) - Hepatitis E virus (HEV) infection is endemic in Germany, where it probably exists as a food-borne zoonosis, according to a report in the December 15th issue of The Journal of Infectious Diseases.

In fact, "HEV seems to be endemic in most industrialized countries and is not restricted to tropical or subtropical regions only," Dr. Ole Wichmann from Robert Koch Institute, Berlin, told Reuters Health. "Physicians in the industrialized countries need to consider hepatitis E as a differential diagnosis in patients with acute liver disease even in the absence of a recent travel history."

Dr. Wichmann and colleagues evaluated epidemiological and molecular characteristics of both travel-associated and autochthonous HEV infections in Germany.

Among the 66 cases analyzed, 45 (68%) had autochthonous HEV infection and 21 (32%) had travel-associated HEV infection, the authors report. The majority of patients in both groups were male.

Symptoms did not differ between cases with travel-related or autochthonous infections, the researchers note.

Consumption of raw or undercooked beef, wild-boar meat, and offal was significantly associated with autochthonous HEV infection, the report indicates, while risk factors for travel-related infection included eating fresh salad, consuming drinks with ice cubes, and drinking tap water.

HEV infection was inversely associated with pet ownership, the investigators say.

"There are two research questions of interest for us," Dr. Wichmann said. "First, it would be important to investigate these meat products (e.g., sold in grocery stores) in order to assess how often they are contaminated with HEV. Second, further studies are needed to identify other routes of HEV transmissions than those identified in our study to explain infections that have not been caused by the consumption of offal or wild boar meat."

Although this study provides further evidence for transmission of HEV as a zoonosis, "neither this study nor previous studies have presented good evidence to explain autochthonous hepatitis E among individuals in industrialized countries who have not reported consumption of undercooked or raw meats or exposure to HEV-reservoir animals," write Dr. Mark H. Kuniholm and Dr. Kenrad E. Nelson from Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, in a related editorial.

"Continued monitoring and evaluation of HEV infections globally is an important public health priority," the editorial concludes.

J Infect Dis 2008;198:1732-1741,1727-1728.