Detection and molecular characterization of hepatitis E virus in food-producing animals in Slovakia

Hepatitis E virus (HEV) is an emerging public health concern in developed countries, with most infections linked to the foodborne transmission of the zoonotic genotype HEV-3. With increasing number of viral hepatitis E cases in human population in Slovakia, knowledge of the situation in the food-producing animal population is becoming increasingly important. Detection of HEV RNA was performed in 290 samples (collected during period of March 2023 to August 2025) from four different species of food-producing animals - pigs, cows, sheep and goats. The presence of HEV RNA was confirmed by real-time RT-PCR in 5 out of 120 (4.2%) fecal samples from pigs in fattening stage originated from a same farm. Prevalence of HEV RNA was relatively lower than in previous findings, what may reflect limitation in sampling strategy. Phylogenetic analyses of selected ORF1 and ORF2 sequences showed that they clustered within genotype HEV-3f (HEV-3 group 1). Presence of this genotype in Slovak pigs supports possibility of zoonotic transmission, since it is most commonly described in the Slovak human patients with severe course of infection. Despite the fact that HEV is circulating in pigs from Slovakia (n = 5/120), we did not detect HEV RNA in cows, sheep or goats (n = 0/170). The absence of HEV RNA in food-producing ruminants has been confirmed during our study period in Slovakia, which point to the fact that these species are probably not the main HEV reservoir compared to pigs. Ongoing research will be essential for tracking HEV circulation across reservoirs.