# First Insight into the Seroprevalence of Hepatitis E Virus and Associated Risk Factors Among Liver Transplant Recipients from Bulgaria

## TL;DR

This study reports the first seroprevalence of Hepatitis E Virus among liver transplant recipients in Bulgaria and identifies a high rate of 34.2%.

## Contribution

The first seroepidemiological study of HEV in Bulgarian liver transplant recipients, revealing a high seroprevalence.

## Key findings

- 34.2% of liver transplant recipients in Bulgaria were seropositive for HEV.
- Higher HEV seropositivity was observed in those over 60 years, though not statistically significant.
- High level of education was a significant risk factor for HEV seropositivity.

## Abstract

Hepatitis E virus (HEV) infection is caused by viruses belonging to the Hepeviridae family. HEV infection can be self-limiting; however, extrahepatic manifestations may be present. The purpose of the current study was to establish the seroprevalence of HEV among Bulgarian liver transplant recipients (LTRs) and to identify associated risk factors.

The present study was conducted between April 1, 2023, and October 30, 2023, at the Military Medical Academy, Sofia, Bulgaria. All serum samples were tested for anti-HEV IgG/IgM using HEV IgG/IgM enzyme-linked immunosorbent assay on Dia.Pro (Milan, Italy). Each participating LTR completed a detailed paper-based closed-ended questionnaire regarding the associated risk factors for HEV infection.

The study included 73 LTRs with a mean age of 47.0 ± 14.0 years. Anti-HEV IgG antibodies were detected in 25 LTRs (34.2%), including 20 males (37.7%) and 5 females (25%). All participants were HEV-IgM negative. HEV seropositivity rates were higher but not statistically significant in LTRs aged >60 years than in those aged <60 years (40% vs. 32.7%). A significant factor by logistic regression was “high level of education” (odds ratio [OR] = 2.917; p = 0.038).

To the best of our knowledge, this is the first seroepidemiological HEV study among LTRs from Bulgaria that found a high seroprevalence (34.2%).