Hepatitis E Virus Occurrence in Pigs Slaughtered in Italy

Area of Science:

• Veterinary Virology
• Food Safety
• Zoonotic Diseases

Background:

• Foodborne transmission of Hepatitis E virus (HEV) in Europe is linked to consuming contaminated pork products.
• Zoonotic HEV genotype 3 is prevalent in European pigs, but its occurrence in slaughterhouses is understudied.

Purpose of the Study:

• To determine the prevalence of HEV RNA in pigs at Italian slaughterhouses.
• To investigate HEV contamination in different pig tissues and identify circulating HEV strains.

Main Methods:

• Real-time RT-PCR was used to detect HEV RNA in feces, liver, diaphragm, and plasma from 585 pigs across 4 abattoirs.
• ELISA was employed to assess total antibodies against HEV.
• Phylogenetic analysis of ORF1 and ORF2 gene fragments was performed.

Main Results:

• HEV RNA was detected in 3.6% (21/585) of pigs.
• Liver was the most frequently HEV RNA-positive tissue, while diaphragm contamination was rare.
• High seroprevalence (76.8%) indicated widespread pig exposure to HEV.
• Phylogenetic analysis identified HEV-3c and a novel unclassified subtype.

Conclusions:

• This study provides crucial data on HEV prevalence in slaughter-aged pigs in Italy.
• Pigs represent a significant reservoir for zoonotic HEV, with varying tissue contamination levels.
• The identification of a novel HEV subtype highlights the need for ongoing surveillance.