Investigation into the presence of Hepatitis E Virus in commercially available venison charcuterie in Scotland

Abstract

Hepatitis E Virus is an RNA virus of the Hepeviridae family that affects hepatocytes and seriously impacts the health of immunocompromised patients. Genotypes 3 and 4 have been circulating in animal populations such as swine and deer in developed countries, causing food borne infections associated with consumption of contaminated animal food products. While HEV has been circulating in European deer populations and causing food borne infections in Asia, its presence in Scottish venison food products has not been investigated. This study assesses 4 ready-to-eat venison charcuterie products for HEV by performing RNA extraction on duplicate samples with a Qiagen RNeasy Midi kit and using Mengovirus as a process control to determine virus recovery by RT-qPCR. This was followed by RT-PCR with previously described HEV primers, and ligation of the suspected positive fragments in a recombinant pGEMT Easy Vector system which was then cloned in competent E. coli cells for propagation. Recombinant plasmids were isolated and subjected to Sanger sequencing. An average RNA extraction efficiency of 5.02% was achieved across all samples, but large deviations between duplicates suggests that further optimisation is necessary in RNA extraction from food products with complex matrices. HEV-sized PCR fragments were detected in 3 out of 4 food products, but the sequencing data showed inefficient ligation of the fragments in the vector, possibly due to low RNA amount and excess of dimerised primers. The likelihood of HEV presence in Scottish venison needs to be investigated further for the detection of transmission routes and the implementation of improved surveillance policies.