Observational Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 7, 2022; 28(37): 5494-5505
Published online Oct 7, 2022. doi: 10.3748/wjg.v28.i37.5494
Insights into hepatitis E virus epidemiology in Croatia
Pavle Jelicic, Thomas Ferenc, Anna Mrzljak, Lorena Jemersic, Natasa Janev-Holcer, Milan Milosevic, Maja Bogdanic, Ljubo Barbic, Branko Kolaric, Vladimir Stevanovic, Mateja Vujica, Zeljka Jurekovic, Jadranka Pavicic Saric, Maja Vilibic, Tatjana Vilibic-Cavlek
Pavle Jelicic, Natasa Janev-Holcer, Department of Environmental Health, Croatian Institute of Public Health, Zagreb 10000, Croatia
Thomas Ferenc, Department of Radiology, Merkur University Hospital, Zagreb 10000, Croatia
Anna Mrzljak, Department of Gastroenterology and Hepatology, University Hospital Center Zagreb, Zagreb 10000, Croatia
Anna Mrzljak, Tatjana Vilibic-Cavlek, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
Lorena Jemersic, Department of Virology, Croatian Veterinary Institute, Zagreb 10000, Croatia
Natasa Janev-Holcer, Department of Social Medicine and Epidemiology, Faculty of Medicine University of Rijeka, Rijeka 51000, Croatia
Milan Milosevic, Department of Occupational and Environmental Health, Andrija Stampar School of Public Health, Zagreb 10000, Croatia
Maja Bogdanic, Tatjana Vilibic-Cavlek, Department of Virology, Croatian Institute of Public Health, Zagreb 10000, Croatia
Ljubo Barbic, Vladimir Stevanovic, Department of Microbiology and Infectious Diseases with Clinic, Faculty of Veterinary Medicine University of Zagreb, Zagreb 10000, Croatia
Branko Kolaric, Department of Gerontology and Social Medicine, Andrija Stampar Teaching Institute of Public Health, Zagreb 10000, Croatia
Mateja Vujica, Institute of Emergency Medicine of Krapina-Zagorje County, Krapina 49000, Croatia
Zeljka Jurekovic, Department of Nephrology, Merkur University Hospital, Zagreb 10000, Croatia
Jadranka Pavicic Saric, Department of Anesthesiology, University Hospital Merkur, Zagreb 10000, Croatia
Maja Vilibic, Department for Social Psychiatry, Psychotherapy and Psychodiagnostics, University Clinical Hospital Center “Sestre Milosrdnice”, Zagreb 10000, Croatia
Author contributions: Jelicic P and Vilibic-Cavlek T conceived the study and wrote the original draft; Ferenc T, Mrzljak A, and Vilibic-Cavlek T wrote the original draft; Janev-Holcer N, Bogdanic M, Mrzljak A, Barbic L, Stevanovic V, Vujica M, Jurekovic Z, Pavicic Saric J, and Vilibic M were involved in the data collection and analysis; Milosevic M and Kolaric B performed the statistical analyses; Jemersic L and Vilibic-Cavlek T revised the manuscript critically; and all authors approved the final version of the manuscript.
Supported by the Croatian Science Foundation (Emerging and Neglected Hepatotropic Viruses after Solid Organ and Hematopoietic Stem Cell Transplantation to Mrzljak A), No. IP-2020-02-7407.
Institutional review board statement: The study was approved by the Ethic Committee of the Croatian Institute of Public Health (protocol code 80327/1-16, approved on 12 February 2016) and School of Medicine University of Zagreb (protocol code 641-01/20-02/01, approved on 22 October 2020).
Informed consent statement: Written informed consent was obtained from all participants included in the study.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: Data sharing available upon request.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Anna Mrzljak, FEBG, PhD, Adjunct Professor, Associate Professor, Department of Gastroenterology and Hepatology, University Hospital Center Zagreb, Kispaticeva 12, Zagreb 10000, Croatia. anna.mrzljak@gmail.com
Received: July 16, 2022
Peer-review started: July 16, 2022
First decision: August 6, 2022
Revised: August 15, 2022
Accepted: September 16, 2022
Article in press: September 16, 2022
Published online: October 7, 2022
Abstract
BACKGROUND

Hepatitis E virus (HEV) is an emerging virus of global health concern. The seroprevalence rates differ greatly according to geographic region and population group.

AIM

To analyze the seroprevalence of HEV in exposed (animal-related professions) and nonexposed populations, as well as solid organ and hematopoietic stem cell transplant patients.

METHODS

Forestry workers (n = 93), hunters (n = 74), and veterinarians (n = 151) represented the exposed population. The general population (n = 126) and pregnant women (n = 118) constituted the control group. Transplant patients included liver transplant recipients (LTRs) (n = 83), kidney transplant recipients (KTRs) (n = 43), and hematopoietic stem cell transplant recipients (HSCRs) (n = 39). HEV immunoglobulin G antibodies were detected using the enzyme-linked immunosorbent assay and confirmed by the immunoblot test.

RESULTS

The HEV seroprevalence significantly differed between groups: Veterinarians 15.2%, hunters 14.9%, forestry workers 6.5%, general population 7.1%, and pregnant women 1.7%. In transplant patients, the seropositivity was highest in LTRs (19.3%), while in KTRs and HSCRs, the seroprevalence was similar to the general population (6.9% and 5.1%, respectively). A significant increase in seropositivity with age was observed from 2.9% in individuals less than 30 years to 23.5% in those older than 60 years. Sociodemographic characteristics (sex, educational level, area of residence, and number of household members), eating habits (game meat, offal, and pork products consumption), and environmental and housing conditions (drinking water supply, type of water drainage/sewer, waste disposal, domestic animals) were not associated with HEV seropositivity. However, individuals who reported a pet ownership were more often seropositive compared to those who did not have pet animals (12.5% vs 7.0%).

CONCLUSION

The results of this study showed that individuals in professional contact with animals and LTRs are at higher risk for HEV infection. In addition, age is a significant risk factor for HEV seropositivity.

Keywords: Hepatitis E virus, Seroprevalence, Veterinarians, Hunters, Forestry workers, Transplant patients, Croatia

Core Tip: Hepatitis E virus (HEV) is an emerging viral pathogen of public health concern. We analyzed the epidemiological characteristics of HEV infection in different groups in Croatia. The highest seroprevalence was reported in professionally exposed individuals such as veterinarians, hunters, and liver transplant recipients. Seropositivity was similar in the general population, forestry workers, kidney transplant patients, and hematopoietic stem cell transplant patients. The lowest seroprevalence was recorded in pregnant women. A significant increase in seroprevalence with age was observed. Pet ownership was also associated with HEV seropositivity. Sex, environmental and housing conditions, and eating habits were not associated with HEV seroprevalence.