The Genetic Analysis of Potential New HEV-3 Subtype Identified on Pig Farm in Slovakia

Hepatitis E virus (HEV) represents the causative agent of acute viral hepatitis in the world. The virus belongs to the genus Paslahepevirus, species Paslahepevirus balayani, which contains 8 different genotypes and at least 14 reference HEV-3 subtypes. Recently we have identified three isolates in a Slovakian pig farm as a new unclassified HEV-3 subtype. The aim of this study was to sequence and analyze additional regions of HEV genome for PER5 isolate, a representative isolate of potential new HEV-3 subtype. The phylogenetic analyses of 749 bp and 828 bp DNA fragments amplified from ORF1 revealed that both sequences fall outside two major clades (3abchij and 3efg) of the HEV-3 genotype as well as the other HEV-3 subtypes. The nucleotide identity with other HEV-3 subtypes indicated low values within the range 79.2–84.1 % as well. The results provide further support for the circulation of a new HEV-3 subtype in the pig farm in Slovakia.