Abstract
Hepatitis E virus (HEV) is an emerging zoonotic pathogen of growing public health concern. HEV genotype 3 is a cause of sporadic human infections in Europe, and is carried by wild boars (Sus scrofa). This study investigated the prevalence of HEV in free-ranging wild boars from different regions of Poland and evaluated the potential risk factors associated with infection. Serum samples (n = 367) were tested serologically for HEV antibodies, and spleen samples (n = 100) for viral RNA using Real-Time quantitative RT-PCR. Detection rates were analysed in relation to geographic origin, sex, and age. HEV-IgG antibodies were detected in 154/367 (41.96%) samples. Viral RNA was identified in 10/100 animals, all of which also tested seropositive. Nested reverse-transcription PCRs amplifying short genomic fragments within ORF1 and ORF2 confirmed five viral sequences: one strain was classified as HEV-3c, related to a human strain from the Netherlands, while the other four belonged to an unclassified subtype similar to sequences reported in wild boar in Europe. Only wild boar density appeared to significantly influence HEV seropositivity. Positive animals were distributed across multiple voivodeships, suggesting widespread environmental circulation.
Data availability
All detailed data are available for request in the corresponding authors. The datasets generated during the current study are available in the NCBI database repository, PX406261-65 and PX435863-PX435865.
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Acknowledgements
We would like to thank all involved vets, foresters, and zootechnicians for their help in collecting samples.
Funding
The publication was financed by the Science Development Fund of the Warsaw University of Life Sciences – SGGW.
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A.D. research design and coordination, collecting samples, data analysis, writing – original draft; D.K. data analysis, statistical analysis, revision of the manuscript, K.M., M.P., E.K. laboratory work, data analysis; K.A., K.F.H. study coordination, data analysis, revision of the manuscript. E.D.L. data analysis; N.D.A. revision of the manuscript; F.S. data analysis; M.L. data analysis; G.F. revision of the manuscript; I.D.B. data analysis, writing – original draft; L.D.S. data analysis; M.G.A. data analysis, writing – original draft, revision of the manuscript. All authors contributed critically to the drafts and gave final approval for publication. All authors have read and agreed to the published version of the manuscript.
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Didkowska, A., Klich, D., Matusik, K. et al. Hepatitis E virus in wild boar from Poland. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42235-2
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DOI: https://doi.org/10.1038/s41598-026-42235-2
