Epidemiology of hepatitis E virus infection in Bulgaria and the Varna region, 2019–2024
DOI:
https://doi.org/10.14748/2xc8bd76Keywords:
hepatitis E virus, epidemiology, surveillance, incidence, BulgariaAbstract
Introduction: The hepatitis E virus (HEV) is a recognized cause of acute viral hepatitis in Europe, predominantly associated with zoonotic transmission of genotype 3. In Bulgaria, HEV has been included in mandatory epidemiological surveillance only since 2019, limiting the availability of systematic national data.
Aim: The aim of this article is to analyse the epidemiological characteristics and temporal patterns of HEV infection in Bulgaria and the Varna region during 2019–2024.
Materials and Methods: A retrospective epidemiological study was conducted using laboratory-confirmed HEV cases reported in the National Information System for Communicable Diseases. Population data were obtained from the National Statistical Institute. Pearson’s χ² test, linear regression for trend analysis and the Edwards test for seasonality assessment were applied. Statistical analysis was performed using SPSS v.27 with significance set at p < 0.05.
Results: A total of 663 HEV cases were registered in Bulgaria, with an average annual incidence of 1.64 per 100,000 population. In the Varna region, 53 cases were reported, corresponding to an incidence of 1.95 per 100,000. Infection predominantly affected males and individuals aged 60 years and older. The case fatality rate was 1.51% nationally and 3.77% in the Varna region. A statistically significant winter seasonal peak was observed. No statistically significant trend in incidence was detected.
Conclusion: The hepatitis E virus is an important etiological agent of acute viral hepatitis in Bulgaria, with epidemiological characteristics comparable to those reported in other European countries. The observed demographic distribution and seasonal pattern support the need for strengthened surveillance and optimized diagnostic strategies.
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Data Availability Statement
The data used in this study are aggregated surveillance data obtained from official national and regional public health sources and are available from the corresponding institutions upon reasonable request.
