Hepatitis E virus: New study shows frequency of contamination in commercial pork
Research scientists from the Institute of Tropical Medicine at the University Hospital of Tubingen have, in cooperation with the Robert Koch Institute, the Federal Institute for Risk Assessment, Berlin and the Hannover Medical School, recently published a study on the detection of the hepatitis E virus in commercial pig livers and pork products in Germany. The results are currently published in the Journal of Viral Hepatitis.
The hepatitis E virus (HEV) is a major cause of acute viral hepatitis and can cause liver failure in several specific patient groups. The pathogen is transmitted via raw meat and contaminated water. In developing countries, the virus is responsible for about 20 million infections and 70,000 deaths per year, and in Germany, too, the number of reported cases has risen sharply over the last ten years. In 2011, 238 cases were reported, in 2019 there were almost 16 times as many (3,727); in August 2020 the number for the current year was already at 2,280 known cases. A vaccine already exists, according to Professor Peter Kremsner, Director and Chairman of the Institute for Tropical Medicine. „Hecolin is an HEV vaccine approved in China. However, the European Medicines Agency has yet to evaluate it for the EU.”
In order to find out whether and how frequently commercial pork products in Germany are contaminated with HEV and, thus, assess the risk of infection, scientists led by Professor Dr. Thirumalaisamy P. Velavan, head of the Molecular Genetics of Infectious Diseases group at the Institute for Tropical Medicine at the University Hospital of Tübingen, and his cooperation partners from the Robert Koch Institute, the Federal Institute for Risk Assessment in Berlin and the Hanover Medical School conducted a study.
Pork livers and pork products from various supermarkets and butcher’s shops in Tubingen, Reutlingen, Stuttgart and Dortmund were tested for HEV RNA. Between October 2019 and February 2020, the researchers took 41 samples of pork livers, 40 of spreadable liver sausages (Delikatessleberwurst, Hausmacher Leberwurst, Gutsleberwurst, Pfälzer Leberwurst, Sahneleberwurst), 40 of liver patés and ten of raw sausages without liver (Braunschweiger Mettwurst, Zwiebelmettwurst, Schinken-Zwiebel-Mettwurst). The samples tested for HEV were mainly from West and Southwest Germany, some from other European countries such as Poland, Austria, Belgium and the Netherlands.
„As the distribution and burden of hepatitis E varies across Europe, the aim was to assess the actual prevalence of HEV-contaminated meat and estimate the risk of exposure and infection. The results of the study show now that more than ten percent of all samples tested are contaminated with HEV,“ Professor Velavan said. The detection of the HEV genome is much higher in pork products than in pork livers; the samples from pork livers show a proportion of five percent, and 13 percent in liver sausages. Taking into account the origin of HEV-positive meat products, no regional prevalence could be determined. „After comparisons with earlier studies, the results indicate that in Germany the prevalence of hepatitis E viruses in food containing pig liver has remained relatively unchanged and very high for the past ten years,“ Professor Velavan sums up. The infectiousness of the virus was not investigated, so detected viruses can already be inactive due to heating during food production.
Institut für Tropenmedizin, Reisemedizin, Humanparasitologie
Prof. Dr. Thirumsalaisamy P. Velavan
Wilhelmstraße 27, 72074 Tübingen
Tel. 07071 29-85981
Pallerla SR, Schembecker S, Meyer CG, Linh LTK, Johne R, Wedemeyer H, Bock CT, Kremsner PG, Velavan TP. Hepatitis E virus genome detection in commercial pork liver and pork meat products in Germany. J Viral Hepat. 2020 Sep 1. doi: 10.1111/jvh.13396. PMID: 32869414