HEPATITIS E IN HUMANS AND PIGS IN BULGARIA (REVIEW)

Aim: The aim of the literature review is to summarize current data on the prevalence of Hepatitis E virus (HEV) in human and
pig population in Bulgaria to 2021. This review is based on reported cases of prevalence of HEV in hospitalized humans and
prevalence of HEV infection in different groups of pig population in Bulgaria.
Methods: The scientific papers and reviews, published in PubMed Databases and Bulgarian medical databases, were analyzed.
Data on the prevalence of Hepatitis E virus in Bulgaria from January 1995 to December 2020 were summarized.
Results: During the period (1995-2020) it was a 16 paper about prevalence of HEV in human and pig population in Bulgaria.
They have been reported 6247 blood serums from hospitalized patients and 1381 serum samples from pigs at different ages
were tested. In total 923 samples (14.7 %) from the hospitalized patients were positive for HEV. AntiHEV-IgG were found in 820
specimens (88.8 %) and HEV-RNA was present in 103 of those (11.2 %). The first data for HEV in pigs in Bulgaria were published
in 2017. In total 846 from 1381 pig serum samples (61.2 %) were positive for antiHev-IgG. Of these, 52 samples (6.1 %) were
from wild boar.
Conclusions: The spread of HEV among the populations of humans and pigs in Bulgaria is worrying. The data from the literature
review are insufficient to establish the relationship between the virus in humans and pigs in Bulgaria. The hepatitis E virus needs
to be considered in the differential diagnosis of acute human hepatitis. The question of its usefulness as an indicator of pork
food safety is also debatable. The development of a unified harmonized strategy for monitoring and control of this zoonotic
agent is imperative.