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Hepatitis E virus (HEV) is an emerging zoonotic virus of public health concern, of which pigs, wild boar and red deer are the main reservoirs. The European Food Safety Authority (EFSA) has recently prioritized the development of monitoring programs of HEV at different stages of the pig food chain, including outdoor pig farming. Pigs managed under these extensive production systems frequently share habitat and natural resources with wild boar and red deer during fattening stages and cross-species transmission of HEV among these species has previously been suggested. In this context, we aimed to (I) to evaluate the risk of HEV circulation within the production phases of extensively raised pigs and at the domestic-wildlife interface, and (II) to identify the genotypes circulating within these hosts. A total of 1452 pigs from seven different pig farms were longitudinally sampled during the breeding, rearing, and fattening production phases. In addition, 138 and 252 sympatric wild boar and red deer, respectively, were analysed. Anti-HEV antibodies were found in 1245 (85.7 %) out of the 1452 Iberian pigs sampled. The seroprevalence was 30.4 % in the breeding phase, 95.4 % in the rearing phase and 97.0 % in the fattening phase. Statistically significant differences (P < 0.05) were found among the three production phases. The seroprevalence was significantly higher (P < 0.001) in fattening pigs compared to those found in sympatric wild boar (31.9 %) and red deer (2.0 %). Three (1.0 %) out of the 293 serum pools analysed were positive for viral RNA. One of them was identified in pigs at the rearing phase (genotype 3 f) and two in wild boar (genotypes 3 f and 3 m). The high seroprevalence detected in extensively raised pigs, together with the detection of the zoonotic HEV-3 f and HEV-3 m subtypes in sympatric domestic and wild swine, highlights the risk of zoonotic transmission and the need to establish surveillance programs and control measures, particularly in breeding and rearing phase, in these epidemiological scenarios., Competing Interests: Declaration of Competing Interest None of the authors of this study has a financial or personal relationship with other people or organizations that could inappropriately influence or bias the content of the paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The hepatitis E virus (HEV) is the main cause of viral acute hepatitis in the world, affecting more than 20 million people annually. During the acute phase of infection, HEV can be detected in various body fluids, which has a significant impact in terms of transmission, diagnosis or extrahepatic manifestations. Several studies have isolated HEV in the genitourinary tract of humans and animals, which could have important clinical and epidemiological implications. So, our main objective was to evaluate the presence of HEV in testis of naturally infected wild boars (Sus scrofa). For it, blood, liver, hepatic lymph node and testicle samples were collected from 191 male wild boars. The presence of HEV was evaluated in serum by PCR, as well as in tissues by PCR and immunohistochemistry. Four animals (2.09%; 95%CI: 0.82-5.26) showed detectable HEV RNA in serum, being confirmed the presence of HEV-3f genotype in three of them by phylogenetic analysis. HEV was also detected in liver and/or hepatic lymph nodes of the four animals by RT-PCR, as well as by immunohistochemistry analysis. Only one of these wild boars also showed detectable viral load in testis, observing HEV-specific labelling in a small number of fibroblasts and some Sertoli cells. Our results confirm the presence of HEV genotype 3 in naturally infected wild boar testis, although no associated tissue damage was evidenced. This study does not allow us to discard semen as a possible source of HEV transmission in suids. Future experimental studies are necessary to evaluate the impact of HEV genotype 3 on fertility and the possibility of transmission through sexual contact in this specie., (© 2022 The Authors. Transboundary and Emerging Diseases published by Wiley-VCH GmbH.)

Autochthonous cases of hepatitis E (HE) associated with zoonotic genotypes HEV-3 and HEV-4 have significantly increased in industrialized countries over the last decade. Suidae are generally recognized as the main reservoirs of these genotypes. Susceptibility to HE virus (HEV) infection and zoonotic potential have also been confirmed in other species, including sheep and goat. However, the information about their role in the epidemiology of HEV remains very scarce. The objective of this study was to assess the prevalence, spatial distribution and risk factors associated with HEV exposure in sheep and goats in southern Spain, the country with the highest census of small domestic ruminants in the European Union. Blood samples from 240 sheep and 240 goats were collected between 2015 and 2017. Sera were analysed in parallel using a commercial double-antigen ELISA and real-time PCR. A total of 38 (7.9%; 95%CI: 5.5-10.3) out of 480 sampled animals showed anti-HEV antibodies. By species, the seroprevalences found in sheep and goats were 2.1% (5/240; 95%CI: 0.3-3.9) and 13.8% (33/240; 95%CI: 9.4-18.1) respectively. Anti-HEV antibodies were found on 19 (59.4%; 95%CI: 42.4-76.4) of the 32 sampled farms. The GEE model showed that species (goat) and number of small ruminants in the farm (≤348 animals and ≥538 animals) were risk factors potentially associated with HEV exposure in small ruminants in the study area. HEV RNA was not detected in any of the 480 (0.0%; 95%CI: 0.0-0.8) tested animals. Our results confirm that sheep and goats are naturally, but not equally exposed to HEV and indicate the widespread spatial distribution of HEV among small ruminant populations in southern Spain. Further studies are required to elucidate the role of sheep and goat in the epidemiology of HEV and their potential implications for public health., (© 2022 The Authors. Zoonoses and Public Health published by Wiley-VCH GmbH.)

In recent decades, cases of autochthonous hepatitis E (HE) have sharply increased in European countries where foodborne transmission is considered the main route of HE virus (HEV) transmission. Although rabbits are considered the main reservoir of the zoonotic HEV-3ra subtype, information on the role of wild lagomorphs in the epidemiology of HEV remains scarce. The aim of this study therefore was to assess the circulation of HEV in European wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis), the most important lagomorph species in Spanish Mediterranean ecosystems. Liver samples from 372 wild rabbits and 78 Iberian hares were analysed using a broad-spectrum RT-PCR that detects HEV genotypes 1-8. None of the 450 lagomorphs tested were positive for HEV infection. To the best of our knowledge, this is the first study to assess HEV circulation in wild rabbits in Spain and the first to evaluate HEV infection in Iberian hares. Our results indicate absence of HEV circulation in wild rabbits and Iberian hares in southern Spain during the study period, which suggests that the risk of transmission of HEV from wild lagomorphs to other species, including humans, is low., (© 2020 Blackwell Verlag GmbH.)

Hepatitis E virus (HEV) is an emerging zoonotic pathogen that has been detected in different animal species. A survey study was carried out to assess HEV infection in non-human primates (NHPs) housed in zoos in Spain. Anti-HEV antibodies were detected in eight of the 181 NHPs tested (4.4%; 95%CI: 1.4-7.4). At least one seropositive animal was detected in five of the 33 species sampled (15.2%). This is the first report of seropositivity in black-and-white ruffed lemurs (Varecia variegata), common chimpanzees (Pan troglodytes), and Barbary macaques (Macaca sylvanus). Anti-HEV antibodies were found in six of the eight zoos included in the study (75.0%). Seroconversion was detected in one chimpanzee, which confirms HEV circulation in one zoo between 2015 and 2016. Seropositivity was significantly higher in hominids than in other NHP families. HEV RNA was not detected in any of the serum samples tested. The results indicate susceptibility of NHPs to HEV infection. Further studies are required to elucidate the role of these species in the epidemiology of HEV., (© 2019 Blackwell Verlag GmbH.)

Simple Summary: The hepatitis E virus (HEV) is an emerging multi-host pathogen whose main reservoir is suids, and the leading cause of acute viral hepatitis in humans. This study evaluates the main long-term drivers of the exposure to HEV are in the wild boar population from Doñana National Park (southwestern Spain) during a 13-year period (2005–2018). For this purpose, we assay sera from 700 wild boar in which anti-HEV antibodies are widely distributed (46.7 ± 3.8%, 327 out of 700 sampled). The observed marked interannual fluctuations could be explained by the variations in the population control of the wild boar during the study period and its impact on abundance rates. Several factors operating in the medium and long-term (individual, environmental, populational and stochastic) and their interplay explained the exposure to HEV in wild boar. The preferential use of certain areas by wild boar together with its abundance and the meteorological conditions may be behind the level of exposure. Wild boar population control remains a challenge at the international level, and an increase of shared pathogen-related conflicts associated with this species is expected, as exemplified by HEV. The hepatitis E virus (HEV) is an emerging zoonotic pathogen whose main reservoir is suids. Most of the ecological and epidemiological aspects of its sylvatic cycle remain unknown. Thus, in this work, we study the drivers of HEV exposure in the wild boar population of Doñana National Park (DNP, southwest Spain) operating in the medium and long-term (2005–2018). Anti-HEV antibodies are widely distributed throughout the wild boar (46.7 ± 3.8%, 327 out of 700 sampled), showing a statistically significant age-increasing pattern. The temporal pattern displayed important interannual fluctuations. This could be mediated by marked variations in the population control of the wild boar, and subsequent changes in abundance rates, and its interplay with climatic conditions; as wet years together with a low abundance of wild boar led to the lowest seroprevalence. The fact that seroprevalence is high during conditions of high abundance, and not affected by rainfall level, is probably due to the increased interactions among the animals, and possibly, the subsequent higher environmental contamination with HEV particles. The proximity to the marshland (the main water body of the study area) is associated with a higher risk of testing positive, which is probably mediated by the preferential use of this area during the dry season and the favourable environmental conditions for the survival of HEV particles. A deeper understanding of the epidemiology of HEV in host communities deserves future research concerning other susceptible species. Most importantly, wild boar population control remains a challenge at the international level, and an increase of shared pathogen-related conflicts associated with this species is expected, as exemplified by HEV. Therefore, surveillance of wild boar diseases, including integrated population monitoring and sustainable population control programmes, will be essential to control the associated risks. [ABSTRACT FROM AUTHOR]