Method for HEV detection in raw pig liver products and its implementation for naturally contaminated food

It is now recognized that Hepatitis E virus (HEV) infection is not confined to developing countries. HEV infection is a growing public health concern in industrialized countries where the disease is mainly autochthonous, caused by HEV genotypes 3 and 4 and is today considered to be zoonotic. HEV causes acute hepatitis in humans, predominantly through contamination of food and water. Due to the low concentrations found in food and water samples, an efficient and rapid virus concentration method is required for routine control. Because of the absence of a reliable cell culture method for the main enteric viruses most commonly involved in the outbreaks, reverse transcription quantitative real time PCR (RT-qPCR) is now widely used for the detection of RNA viruses in all types of samples. The aim of this study was to provide a rapid and sensitive method for detecting HEV in pig liver products. A method which includes a virus concentration step by PEG has been chosen from 9 protocols to be further validated. We used a one-step duplex RT-qPCR for detecting HEV and the murine norovirus (MNV-1) used as a process control for monitoring the quality of the whole extraction procedure. The mean recovery rates of the HEV and MNV-1 obtained from pig liver sausages were respectively 3.94% and 2.92%, increasing in figatelli to 18.38% and 13.11% respectively. This method also proved to be effective for HEV detection in naturally contaminated foodstuffs containing raw pig liver.