Monitoring of Hepatitis E Virus in Wild Lagomorphs in Spanish Mediterranean Ecosystems

Abstract

Hepatitis E virus (HEV) is an emerging zoonotic pathogen in Europe. Even though swine species are considered the main host of the zoonotic HEV-3 genotype, rabbits are recognized as the main reservoir of the divergent HEV-3ra subtype. However, the role of wild lagomorphs in the epidemiology of this virus in Mediterranean ecosystems is under debate. The aims of this study were to assess exposure of HEV in wild rabbit (Oryctolagus cuniculus) and Iberian hare (Lepus granatensis) populations in southern Spain and to determine potential risk factors associated with HEV exposure in these species. Between 2018 and 2021, blood and fecal samples from 370 wild rabbits and 60 Iberian hares were collected. A total of 29 (6.7%; 95%CI: 4.4–9.1) out of 430 sampled animals showed anti-HEV antibodies. By species, the seroprevalences in wild rabbit and Iberian hare were 6.8% (29/370; 95%CI: 4.2–9.3) and 6.7% (4/60; 95%CI: 0.4–13.0), respectively. Seropositive animals were detected on 17 (26.2%; 95%CI: 15.4–36.8) of the 65 sampled hunting estates. The generalized estimating equations model showed that geographical area was a risk factor potentially associated with HEV exposure in wild lagomorphs in the study region. HEV RNA was not detected in any of the 242 (0.0%; 95%CI: 0.0–1.5) fecal samples tested. This is the first large-scale serosurvey performed in wild rabbits in the Iberian Peninsula and in Iberian hares worldwide. Our results provide evidence of low, widespread, and heterogeneous distribution of HEV among wild rabbit and Iberian hare populations in Spanish Mediterranean ecosystems, which indicates a limited role of wild lagomorphs in the maintenance of the virus and a low risk of transmission of HEV to other species, including humans.