Hepatitis E Virus Detection in Swine Slurries of Abruzzo: Considerations on Virus Occurrence and Workers’ Exposure

Pigs and wild boars are the main reservoirs of the Hepatitis E virus (HEV). In Abruzzo, the majority of pigs is reared in a few specialised structures, mainly devoted to animal reproduction and fattening. As seroprevalence studies on blood donors highlight significant exposure to the virus in Abruzzo, the One Health FOOD-WAT HEV project has focused on HEV presence in slurry samples from specialised rearing units to underpin the factors potentially influencing virus circulation in pig farms. Four sampling campaigns were conducted in 19 intensive swine farming units throughout the Abruzzo Region in July and November 2021, May and November 2022. Slurry samples were processed by concentration, nucleic acid extraction and nested RT-PCR to detect HEV presence. Frequency analysis and binary logistic regression focused on any possible connection between breeding site characteristics, geographical location of the farm, and HEV presence. HEV detection in swine slurry revealed a significant virus circulation throughout the Abruzzo territory: 18.9% of the collected samples resulted positive for HEV, almost all of which were from the sampling in May 2022. The χ2test revealed a significant relation between HEV detection and the housing structures with partly slatted floors, which were nearly fourfold more likely to provide HEV-positive slurry samples. Such findings underline the importance of good farming practices (i.e., adoption of biosafety procedures and rapid manure removal from the pens) as the first countermeasure to reduce workers’ exposure.