Detection and Characterization of Hepatitis E Virus from Pig Livers Sold in Local Butcher Shops in Southeastern Germany – A Possible Source of Infection for Humans?

Introduction: Hepatitis E virus (HEV) has been identified as an emerging cause of infectious hepatitis over the last years in developed countries. In contrast to travel associated hepatitis E, zoonotic sources of infection are suspected for autochthonous cases in Europe. Since pigs are known reservoirs of HEV, we tested pig livers sold in local butcher shops in Southeastern Germany for the presence of Hepatitis E virus.

Methods: We purchased 200 pig liver samples in 81 butcher shops and grocery stores in the city of Regensburg and its surroundings. Nucleic acid preparations were tested by quantitative real-time PCR (RT-qPCR) capable of detecting all relevant HEV genotypes. HEV isolates from positive samples were further classified by partial sequencing of ORF1 and ORF2 regions in the HEV genome and phylogenetic analysis.

Results: Among the 200 tested liver samples, one was positive for HEV RNA (0.5%). Sequence determination and phylogenetic analysis allowed the novel isolate to be classified as HEV genotype 3, subgenotype 3a. Close homology was found to precharacterized isolates from infected humans and pigs.

Discussion: High sequence homology of the novel HEV isolate as compared to precharacterized isolates of human and pig origin supports the suggested role of undercooked pig products in food as source of zoonotic HEV infection. It remains to be clarified if this mechanism of transmission is responsible for the observed high anti-HEV IgG seroprevalence (up to 30%) in the European population.

HEV - Hepatitis E Virus - PCR - Pig Livers - Southeastern Germany