Molecular Investigation of Hepatitis E Virus Occurrence in Liver and Muscle Tissues of Wild Boars in Northern Italy

Hepatitis E Virus (HEV) has emerged as a significant public health concern in various European countries, including Italy. Several genotypes have been recognized, some of those are zoonotic. The primary mode of human infection of these genotypes is through the consumption of contaminated uncooked or undercooked animal derived food products. Wild boar has been identified as a crucial host for HEV virus with hunting and consumption of wild boar liver and muscle tissue thus contributing to transmission of the virus. Based on these premises, and considering the frequent consumption of wild boar meat in Italy, this thesis aimed to develop a sensitive diagnostic protocol using an RT-qPCR assay for the detection of the HEV virus in animal tissues. Following validation, the designed assay demonstrated the ability to detect as little as 1 copy of the viral genome per µL of extracted sample. The test was applied to a preliminary investigation performed on samples collected in the Verona province, where wild boar hunting and consumption is common. A total of 112 tissue samples, consisting of 56 liver and 56 muscle sample were analyzed to detect the presence of HEV RNA and compare the diagnostic sensitivity in liver (the main virus target tissue) and muscle (a tissue that must be sampled during post-mortem inspection by public veterinarians). None of the tested samples were positive, suggesting a low prevalence of the virus in the wild population. This contrasts with findings from other studies conducted in central and southern Italy but aligns with preliminary data obtained by other groups in northern Italy. Although this may indicate the influence of host population characteristics and a potentially limited risk in northern Italy, further studies are underway to confirm these findings and expand on them to better characterize the molecular epidemiology of HEV in northern Italy.