Circulation of genotype 4 hepatitis E virus in Europe: first autochthonous hepatitis E infection in France

Epidemiology of Hepatitis E

Hepatitis E virus (HEV) is globally prevalent with relatively high percentages of anti-HEV immunoglobulin G-positive individuals in the populations of developing and developed countries. There are two distinct epidemiological patterns of hepatitis E. In areas with high disease endemicity, primarily developing countries in Asia and Africa, this disease is caused mainly by genotypes HEV-1 or HEV-2; both genotypes transmit predominantly through contaminated water and occur as either outbreaks or sporadic cases of acute hepatitis. The acute hepatitis has the highest attack rate in young adults and is particularly severe among pregnant women. In developed countries, sporadic cases of locally acquired HEV-3 or HEV-4 infection are observed. The reservoir of HEV-3 and HEV-4 is believed to be animals, such as pigs, with zoonotic transmission to humans. The affected persons are often elderly, and persistent infection has been well documented among immunosuppressed persons. A subunit vaccine has been shown to be effective in preventing clinical disease and has been licensed in China.

Clinical features of hepatitis E infections in patients with hematologic disorders

Hepatitis E virus is increasingly being reported to cause chronic infection in immunocompromised patients. However, less is known about patients with an underlying hematologic disease. In particular, the impact of hepatitis E infection on oncological therapy has been poorly described. In this retrospective single-center study, we analyzed 35 hematologic patients with hepatitis E, including 20 patients under active oncological treatment and 15 patients who were in the posttreatment follow-up or under active surveillance. The primary aim was to describe the clinical courses with particular focus on any hepatitis E-related therapy modifications of cancer-directed therapy. In the majority (60%) of patients who were under active oncological treatment, hepatitis E-related therapy modifications were made, and 25% of deaths were due to progression of the hematologic disease. In patients receiving concomitant oncological treatment, no hepatitis Erelated deaths occurred. In contrast, two patients in the follow-up group died from hepatitis E-associated acute-onchronic liver failure. Chronic hepatitis E was observed in 34% of all cases and 43% received ribavirin therapy; of those, 27% achieved a sustained virological response. CD20-directed therapy was the only independent risk factor for developing chronic hepatitis E. We conclude that CD20-directed treatment at any time point is a risk factor for developing chronic hepatitis E. Nevertheless, since mortality from the progression of hematologic disease was higher than hepatitis E-related mortality, we suggest careful case-by-case decisions on modifications of cancer treatment. Patients in the posttreatment follow-up phase may also suffer from severe courses and hepatitis E chronicity occurs as frequently as in patients undergoing active therapy.

Distribution and phylogenetics of hepatitis E virus genotype 4 in humans and animals

BACKGROUND

Worldwide, hepatitis E virus (HEV) infection is considered a significant public health concern. In particular, HEV genotype 4 (HEV-4) has spread to more areas and host species. In this study, we describe the global distribution of HEV-4 and characterize HEV-4 subtypes by host, country and year of isolation.

METHODS

We retrospectively collected HEV-4 sequences available before December 31, 2019, in GenBank. HEV-4 and its subtypes were determined using phylogenetic comparison with HEV reference sequences. Information on the isolation of the sequences was extracted from the GenBank or original publications. Temporal, spatial and host characteristics of the sequences were summarized and nucleotide similarity was calculated based on five amplified fragments within HEV genome, stratified by host, country and year.

RESULTS

A total of 2295 HEV-4 complete and partial nucleotide sequences were studied. The majority (92.7%) was isolated in China's mainland, Japan, Hong Kong and France. A total of 20 animal hosts were documented, though swine remained predominant (71.7%). Globally, prevalent HEV-4 subtypes changed remarkably over the last 18 years. Subtypes 4a, 4b, 4d and 4h were most commonly isolated (80.3%). Subtypes 4c, 4e, 4f, 4g and 4i remained limited in temporal distribution. High nucleotide similarities were observed between the sequences amplified in HEV ORF2, in the same and neighbouring countries, and in similar animal hosts.

CONCLUSION

China and Japan are endemic for HEV-4, and have all the subtypes. In Europe, France has a high prevalence of HEV-4. Increases in affected areas and animal hosts imply consistent cross-border and cross-species transmission.

Analyses of Clinical and Biological Data for French and Belgian Immunocompetent Patients Infected With Hepatitis E Virus Genotypes 4 and 3

Hepatitis E virus (HEV) genotypes 3 and 4 are the major causes of acute hepatitis in industrialized countries. Genotype 3 is mainly found in Europe and America, while genotype 4 is predominant in Asia. Several Japanese studies have suggested that genotype 4 is more virulent than genotype 3. We investigated this aspect by analyzing the clinical and biological data for 27 French and Belgian immunocompetent patients infected with HEV genotype 4. Their infections were probably acquired locally, since none of these patients reported traveling outside France or Belgium during the 2–8 weeks before symptoms onset. Each patient was matched for age (±5 years) and gender with two patients infected with HEV genotype 3. Bivariate analysis indicated that the HEV genotype 4-infected patients had significantly higher alanine aminotransferase (ALT) (2067 IU/L) and aspartate aminotransferase (AST) (1581 IU/L) activities and total bilirubin concentrations (92.4 μmol/L) than did those infected with HEV genotype 3 (1566 IU/L, p = 0.016; 657 IU/L, p = 0.003 and 47 μmol/L, p = 0.046) at diagnosis. In contrast, more patients infected with HEV genotype 3 reported dark urine (71% vs. 39%, p = 0.02) and experienced asthenia (89% vs. 58%, p < 0.01) than did those infected with HEV genotype 4. Two HEV genotype 4-infected patients died of multi-organ failure, while none of the genotype 3-infected patients died (p = 0.035). Finally, stepwise regression analysis retained only a greater increase in ALT (odds-ratio: 1.0005, 95% confidence interval: 1.00012–1.00084) and less frequent fever (odds-ratio = 0.1244; 95% confidence interval: 0.01887–0.82020) for patients infected with HEV genotype 4. We conclude that HEV-4 infections are likely to be associated with higher ALT activity than HEV-3 infections. Additional immunological and virological studies are required to confirm these findings and better understand the influence, if any, of genotype on HEV pathophysiology.

Phylogeography and evolutionary history of hepatitis E virus genotype 3 in Argentina

BACKGROUND

Few studies about the evolutionary history of the hepatitis E virus (HEV) have been conducted. The aim of our work was to investigate and make inferences about the origin and routes of dispersion of HEV-3 in Argentina.

METHODS

Phylogenetic, coalescent and phylogeographic analyses were performed using a 322-bp ORF2 genomic fragment of all HEV-3 sequences with known date and place of isolation published at GenBank until May 2018 (n=926), including 16 Argentinian sequences (isolated from pigs, water and humans).

RESULTS

Phylogenetic analysis revealed two clades within HEV-3: abchij and efg. All Argentinian samples were grouped intermingled within clade 3abchij. The coalescent analysis showed that the most recent common ancestor for the clade 3abchij would have existed around the year 1967 (95% highest posterior density (HPD): 1963-1970). The estimated substitution rate was 1.01×10-2 (95%HPD: 9.3×10-3-1.09×10-2) substitutions/site/y, comparable with the rate previously described. The phylogeographic approach revealed a correspondence between phylogeny and place of origin for Argentinian samples, suggesting many HEV introductions in the country, probably from Europe and Japan.

CONCLUSIONS

This is the first evolutionary inference of HEV-3 that includes Argentinian strains, showing the circulation of many HEV-3 subtypes, obtained from different sources and places, with recent diversification processes.

ACCESSION NUMBERS

[KX812460], [KX812461], [KX812462], [KX812465], [KX812466], [KX812467], [KX812468], [KX812469].

Advances in Hepatitis E Virus Biology and Pathogenesis

Hepatitis E virus (HEV) is one of the causative agents for liver inflammation across the world. HEV is a positive-sense single-stranded RNA virus. Human HEV strains mainly belong to four major genotypes in the genus Orthohepevirus A, family Hepeviridae. Among the four genotypes, genotype 1 and 2 are obligate human pathogens, and genotype 3 and 4 cause zoonotic infections. HEV infection with genotype 1 and 2 mainly presents as acute and self-limiting hepatitis in young adults. However, HEV infection of pregnant women with genotype 1 strains can be exacerbated to fulminant hepatitis, resulting in a high rate of case fatality. As pregnant women maintain the balance of maternal-fetal tolerance and effective immunity against invading pathogens, HEV infection with genotype 1 might dysregulate the balance and cause the adverse outcome. Furthermore, HEV infection with genotype 3 can be chronic in immunocompromised patients, with rapid progression, which has been a challenge since it was reported years ago. The virus has a complex interaction with the host cells in downregulating antiviral factors and recruiting elements to generate a conducive environment of replication. The virus-cell interactions at an early stage might determine the consequence of the infection. In this review, advances in HEV virology, viral life cycle, viral interference with the immune response, and the pathogenesis in pregnant women are discussed, and perspectives on these aspects are presented.

Laboratory-based Surveillance and Clinical Profile of Sporadic HEV Infection in Shanghai, China

The study aimed to describe the epidemiological, virological and clinical features of sporadic HEV infection in eastern China. A total of 6112 patient sera were tested for anti-HEV IgG or anti-HEV IgM during one consecutive year (between August 2018 and July 2019). HEV RNA presence was evaluated by RT-PCR and HEV sequences were phylogenetically analyzed. Clinical features of confirmed HEV-infected patients were delineated. The sero-positivity rate of anti-HEV IgG maintained stable around 40%, while an obvious winter spike of anti-HEV IgM prevalence was observed. A total of 111 patients were confirmed of HEV viremia by molecular diagnosis. Subtype 4d was predominant. Phylogenetic analyses suggest that certain strains circulate across species and around the country. Subjects with confirmed current HEV infection had a high median age (58 years) and males were predominant (62.2%). Most patients presented with jaundice (75.7%) and anorexia (68.0%). Significantly elevated levels of liver enzymes and bilirubin were observed. Remarkably, the baseline bilirubin level was positively correlated with illness severity. Pre-existing HBV carriage may deteriorate illness. The clinical burden caused by locally acquired HEV infection is increasing. Surveillance should be enforced especially during the transition period from winter to spring. Patients with higher level of bilirubin at disease onset had slower recovery from HEV infection.

Prevalence and genotype/subtype distribution of hepatitis E virus (HEV) among wild boars in Japan: Identification of a genotype 5 HEV strain

To further investigate the prevalence of hepatitis E virus (HEV) infection and characterize HEV genomes among Japanese wild boars (Sus scrofa leucomystax), 1880 boars captured in 17 prefectures in Japan from 2013 to 2019 were studied. Overall, anti-HEV IgG was detected in 8.9 % and HEV RNA was detected in 3.9 % of boars, which was comparable with our previous studies during 2003-2013 (10.3 % and 3.5 %, respectively). Among 74 boar HEV strains obtained from infected boars in the present study, 50 (68 %) were classified into genotype 3 (3a and 3b), 23 (31 %) were classified into genotype 4 (4i), and the remaining strain (wbJGF_19-1) was classified into genotype 5. The wbGF_19-1 strain shared 92.7 % identity over the entire genome with the prototype genotype 5 strain (JBOAR135-Shiz09). The identification of the second genotype 5 HEV strain in a place that is located only 100 km from the site at which JBOAR135-Shiz09 was identified, suggests that genotype 5 HEV circulates within a relatively close range in Japan. Genetically similar HEV strains forming a clade were identified from wild boars living in each area during the observation period of 11-13 years, although the nucleotide sequence changed gradually, accounting for up to 3.4-3.6 % within the 412-nucleotide ORF2 sequence. Eight groups of boars with a cluster of HEV infections were observed, consisting of two, three or four infected offspring, presumably born to the same mother or offspring with their mother. These results suggest that wild boars continue to be important reservoirs for HEV infection in humans in Japan.

The First Case Report of Acute Symptomatic HEV Genotype 4 Infection in an HIV-positive Patient in Japan

Hepatitis E virus (HEV) is a common cause of acute hepatitis. Four major genotypes of HEV have been studied, with genotype 4 being the predominant genotype across Asia. We herein describe the case of a 50-year-old man with a history of human immunodeficiency virus (HIV) infection who was admitted with acute transaminitis. Serum anti-HEV-IgA and HEV-RNA were detected at the time of presentation and further testing revealed HEV genotype 4. To the best of our knowledge, this represents the first clinical case report of acute symptomatic HEV genotype 4 infection in an HIV-positive patient in Japan.

Swine hepatitis E virus: Cross-species infection, pork safety and chronic infection

Swine hepatitis E virus (swine HEV) belongs to the species Orthohepevirus A within the genus Orthohepevirus in the family Hepeviridae. Four different genotypes of swine HEV within the species Orthohepevirus A have been identified so far from domesticated and wild swine population: genotypes 3 (HEV-3) and 4 (HEV-4) swine HEVs are zoonotic and infect humans, whereas HEV-5 and HEV-6 are only identified from swine. As a zoonotic agent, swine HEV is an emerging public health concern in many industrialized countries. Pigs are natural reservoir for HEV, consumption of raw or undercooked pork is an important route of foodborne HEV transmission. Occupational risks such as direct contact with infected pigs also increase the risk of HEV transmission in humans. Cross-species infection of HEV-3 and HEV-4 have been documented under experimental and natural conditions. Both swine HEV-3 and swine HEV-4 infect non-human primates, the surrogates of man. Swine HEV, predominantly HEV-3, can establish chronic infection in immunocompromised patients especially in solid organ transplant recipients. The zoonotic HEV-3, and to lesser extent HEV-4, have also been shown to cause neurological diseases and kidney injury. In this review, we focus on the epidemiology of swine HEV, host and viral determinants influencing cross-species HEV infection, zoonotic infection and its associated pork safety concern, as well as swine HEV-associated chronic infection and neurological diseases.

Hepatitis E Virus in Pigs from Slaughterhouses, United States, 2017-2019

Hepatitis E virus (HEV) RNA was detected in 6.3% and HEV IgG in 40% of 5,033 serum samples from market-weight pigs at 25 slaughterhouses in 10 US states. The prevalent HEV genotype was zoonotic genotype 3, group 2. Blood of HEV-viremic pigs from slaughterhouses may contaminate pork supply chains.

Genetic Variability and Evolution of Hepatitis E Virus

Hepatitis E virus (HEV) is a single-stranded positive-sense RNA virus. HEV can cause both acute and chronic hepatitis, with the latter usually occurring in immunocompromised patients. Modes of transmission range from the classic fecal–oral route or zoonotic route, to relatively recently recognized but increasingly common routes, such as via the transfusion of blood products or organ transplantation. Extrahepatic manifestations, such as neurological, kidney and hematological abnormalities, have been documented in some limited cases, typically in patients with immune suppression. HEV has demonstrated extensive genomic diversity and a variety of HEV strains have been identified worldwide from human populations as well as growing numbers of animal species. The genetic variability and constant evolution of HEV contribute to its physiopathogenesis and adaptation to new hosts. This review describes the recent classification of the Hepeviridae family, global genotype distribution, clinical significance of HEV genotype and genomic variability and evolution of HEV.

Hepatitis E Virus: A New Foodborne Zoonotic Concern

Hepatitis E virus (HEV) is an enteric nonenveloped single-stranded RNA virus. Among the mammalian lineages, four genotypes are associated to human infection: genogroups 1 and 2 infect only humans and are mainly found in developing countries, while genogroups 3 and 4 are zoonotic, being found in a variety of animal species including pigs, and are autochthonous in developed countries. HEV infection can result in liver damage and with genotypes 1 and 2 symptoms can be particularly severe in pregnant women, with a high lethality ratio. Several cases of foodborne transmission of hepatitis E have been reported, often involving consumption of meat, especially raw or undercooked. Information is lacking on the exact extent of foodborne transmission of HEV.

Absence of zoonotic hepatitis E virus infection in Flemish dairy cows

Recently, infectious HEV particles were discovered in milk and fecal samples of dairy cows in China. Given the recent increase of autochthonous HEV infections in Europe, we wanted to assess whether cows constitute an HEV reservoir in this region and hence may be responsible for the advance of HEV through consumption of cow produce. To verify the zoonotic risk cows potentially pose towards European consumers, we screened >10% of dairy milk farms in Flanders, Belgium for the presence of HEV. A quarter of these housed both cows and pigs, the latter a well-known reservoir for HEV. Milk and fecal samples were analyzed for the presence of HEV RNA and HEV-specific antibodies. Despite the fact that HEV is circulating amongst pig farms in Flanders and proof of active HEV infection in the pigs of at least one of the mixed farms included in our study, we could not detect any sign of active or past HEV infection in cows. The HEV prevalence in our study was 0%, with a 99.99% confidence interval (CI) for HEV RNA and anti-HEV antibody of [0%-2.30%] and [0%-4.23%] respectively. Our results suggest that, at least in Flanders, cows are not an HEV reservoir and hence do not pose a major health risk towards humans.

Selected Viruses Detected on and in our Food

PURPOSE OF REVIEW

The purpose of this review is to provide an update on recent literature and findings concerning selected foodborne viruses. Two groups of viruses were selected: (a) the most important viruses contaminating food, based on numbers of publications in the last 5 years and (b) viruses infecting sources of food that might have an impact on human health.

RECENT FINDINGS

Important foodborne viruses such as norovirus, hepatitis A and rotavirus are usually "only" contaminating food and are detected on the surface of foodstuffs. However, they are threats to human public health and make up for the majority of cases. In contrast, the meaning of viruses born from within the food such as natural animal and plant viruses is still in many cases unknown. An exception is Hepatitis E virus that is endemic in pigs, transmitted via pork meat and is recognised as an emerging zoonosis in industrialised countries.

SUMMARY

Even though the clinical meaning of "new" foodborne viruses, often detected by next generation sequencing, still needs clarification, the method has great potential to enhance surveillance and detection particularly in view of an increasingly globalised food trade.

Detection and Characterization of Hepatitis E Virus in Goats at Slaughterhouse in Tai'an Region, China

Background

Hepatitis E virus (HEV) is a significant pathogen of viral hepatitis and can be transmitted through fecal-oral route. Epidemiological data concerning HEV in goats, however, are relatively sparse to date. Here, the prevalence and characteristics of HEV isolated from goats at slaughterhouse were investigated in Tai'an region, China.

Methods

Anti-HEV immunoglobulin G (IgG) in blood samples and HEV RNA in the liver samples were determined by using an enzyme-linked immunosorbent assay (ELISA) and a nested reverse transcription polymerase chain reaction (RT-PCR), respectively. In addition, partial nucleotide sequences of open reading frame 2 (ORF-2) of HEV isolates were analyzed.

Results

Fifty goat blood samples (46.7%, 50/120) were masculine for anti-HEV IgG. HEV RNA was detected in 2 liver samples (4.0%, 2/50) and belonged to genotype 4 subtype 4 h, with high identity (91.2-93%) with cow HEV strains detected in the same province, China.

Conclusions

These findings demonstrated that goats may be an important reservoir for HEV and can become a major source of HEV infection in humans via food chain.

Epidemiology of Hepatitis E

Hepatitis E virus (HEV) is globally prevalent with relatively high percentages of anti-HEV immunoglobulin G-positive individuals in the populations of developing and developed countries. There are two distinct epidemiologic patterns of hepatitis E. In areas with high disease endemicity, primarily developing countries in Asia and Africa, this disease is caused mainly by genotype 1 or 2 HEV, both of which transmit predominantly through contaminated water and occur as either outbreaks or as sporadic cases of acute hepatitis. The acute hepatitis caused by either of these two genotypes has the highest attack rate in young adults, and the disease is particularly severe among pregnant women. In developed countries, sporadic cases of locally acquired genotype 3 or 4 HEV infection are observed. The reservoir of genotype 3 and 4 HEV is believed to be animals, such as pigs, with zoonotic transmission to humans. The affected persons are often elderly, and persistent infection has been well documented among immunosuppressed persons. A subunit vaccine has been shown to be effective in preventing clinical disease and has been licensed in China.

Hepatitis E in Italy: A silent presence

Hepatitis E virus (HEV) was discovered in the 1980s and has been considered as being confined to developing countries. The purpose of this critical review was to determine the reported HEV seroprevalence rates in Italy, to identify predisposing factors and individuals at risk and to assess possible importation of HEV by immigrants. A critical review of 159 articles published in PubMed from 1994 to date was done. Only 27 original reports of 50 or more subjects, written in the English or Italian language, were included. Over three decades, the HEV seroprevalence varied from 0.12% to 49%, with the highest rates being reported from the central region of Italy. Risk factors included ingestion of raw pork or potentially contaminated food. The seroprevalence among immigrants ranged from 15.3% to 19.7% in Apulia. Italy has a population of 60656000; the total number of individuals surveyed was only 21.882 (0.036%). A national epidemiological survey program is needed to capture more comprehensive seroprevalence data.

Review article: hepatitis E-a concise review of virology, epidemiology, clinical presentation and therapy

BACKGROUND

Hepatitis E virus (HEV) is a leading cause of acute icteric hepatitis and acute liver failure in the developing world. During the last decade, there has been increasing recognition of autochthonous (locally acquired) HEV infection in developed countries. Chronic HEV infection is now recognised, and in transplant recipients this may lead to cirrhosis and organ failure.

AIM

To detail current understanding of the molecular biology of HEV, diagnostic and therapeutic strategies and propose future directions for basic science and clinical research.

METHODS

PubMed was searched for English language articles using the key words "hepatitis E", "viral hepatitis", "autochthonous infection", "antiviral therapy", "liver transplantation", "acute", "chronic", "HEV", "genotype", "transmission" "food-borne", "transfusion". Additional relevant publications were identified from article reference lists.

RESULTS

There has been increasing recognition of autochthonous HEV infection in Western countries, mainly associated with genotype 3. Chronic HEV infection has been recognised since 2008, and in transplant recipients this may lead to cirrhosis and organ failure. Modes of transmission include food-borne transmission, transfusion of blood products and solid organ transplantation. Ribavirin therapy is used to treat patients with chronic HEV infection, but new therapies are required as there have been reports of treatment failure with ribavirin.

CONCLUSIONS

Autochthonous HEV infection is a clinical issue with increasing burden. Future work should focus on increasing awareness of HEV infection in the developed world, emphasising the need for clinicians to have a low threshold for HEV testing, particularly in immunosuppressed patients. Patients at potential risk of chronic HEV infection must also be educated and given advice regarding prevention of infection.

Public health risks associated with hepatitis E virus (HEV) as a food-borne pathogen

Hepatitis E virus (HEV) is an important infection in humans in EU/EEA countries, and over the last 10 years more than 21,000 acute clinical cases with 28 fatalities have been notified with an overall 10-fold increase in reported HEV cases; the majority (80%) of cases were reported from France, Germany and the UK. However, as infection in humans is not notifiable in all Member States, and surveillance differs between countries, the number of reported cases is not comparable and the true number of cases would probably be higher. Food-borne transmission of HEV appears to be a major route in Europe; pigs and wild boars are the main source of HEV. Outbreaks and sporadic cases have been identified in immune-competent persons as well as in recognised risk groups such as those with pre-existing liver damage, immunosuppressive illness or receiving immunosuppressive treatments. The opinion reviews current methods for the detection, identification, characterisation and tracing of HEV in food-producing animals and foods, reviews literature on HEV reservoirs and food-borne pathways, examines information on the epidemiology of HEV and its occurrence and persistence in foods, and investigates possible control measures along the food chain. Presently, the only efficient control option for HEV infection from consumption of meat, liver and products derived from animal reservoirs is sufficient heat treatment. The development of validated quantitative and qualitative detection methods, including infectivity assays and consensus molecular typing protocols, is required for the development of quantitative microbial risk assessments and efficient control measures. More research on the epidemiology and control of HEV in pig herds is required in order to minimise the proportion of pigs that remain viraemic or carry high levels of virus in intestinal contents at the time of slaughter. Consumption of raw pig, wild boar and deer meat products should be avoided.

Seroepidemiology and molecular characterization of hepatitis E virus infection in swine and occupationally exposed workers in Punjab, India

Hepatitis E virus (HEV) has two discrete epidemiological patterns: waterborne epidemics in developing countries only, caused by HEV genotype I, and sporadic zoonotic outbreaks in developing and developed countries caused by genotypes III and IV. This study was designed to investigate seroprevalence, molecular detection and the characterization of HEV by nested RT-PCR in swine as well as the occupational risk to exposed human population in Punjab state of north-western India. The occupational risk-exposed group comprised of swine farmers (organized - mixed feed feeders and unorganized - swill feeders), slaughterhouse workers, sewage workers and veterinary internes. During the study period, blood and faecal samples were collected from 320 swine and 360 humans with both high and low occupational exposure risks. The overall seroprevalence of swine HEV was 65.00%, with a significantly higher seropositivity in growing pigs (2-8 months of age). The prevalence of HEV RNA in swine faecal samples by nRT-PCR was 8.75% with a significantly higher detection in swill-fed pigs. With humans in the high occupational exposure risk population, significantly higher anti-HEV IgG seropositivity was observed (60.48%) as compared to control population (10.71%). Strong evidence of association between human anti-HEV IgG seropositivity and certain occupational exposure risk groups was observed (p < 0.05). This indicates that unorganized swine farmers, slaughterhouse workers and sewage workers have higher odds of HEV infection in this study region. Percentage of nucleotide similarity between swine and human HEV isolates was less than that found in countries with zoonotic HEV outbreaks. Molecular characterization revealed the circulation of G IV and G I genotypes among swine and human population in Punjab state, respectively.

Hepatitis E Virus in Industrialized Countries: The Silent Threat

Hepatitis E virus (HEV) is the main cause of acute viral hepatitis worldwide. Its presence in developing countries has been documented for decades. Developed countries were supposed to be virus-free and initially only imported cases were detected in those areas. However, sporadic and autochthonous cases of HEV infection have been identified and studies reveal that the virus is worldwide spread. Chronic hepatitis and multiple extrahepatic manifestations have also been associated with HEV. We review the data from European countries, where human, animal, and environmental data have been collected since the 90s. In Europe, autochthonous HEV strains were first detected in the late 90s and early 2000s. Since then, serological data have shown that the virus infects quite frequently the European population and that some species, such as pigs, wild boars, and deer, are reservoirs. HEV strains can be isolated from environmental samples and reach the food chain, as shown by the detection of the virus in mussels and in contaminated pork products as sausages or meat. All these data highlight the need of studies directed to control the sources of HEV to protect immunocompromised individuals that seem the weakest link of the HEV epidemiology in industrialized regions.

Excretion of infectious hepatitis E virus into milk in cows imposes high risks of zoonosis

Hepatitis E virus (HEV) represents the main cause of acute hepatitis worldwide. HEV infection in immunocompromised patients involves a high risk for the development of chronic hepatitis. Because HEV is recognized as a zoonotic pathogen, it is currently believed that swine is the primary reservoir. However, this is not sufficient to justify the strikingly high seroprevalence of HEV in both developing and Western countries. Thus, this study aimed to identify new zoonotic sources that bear a high risk of transmission to humans. We collected fecal, blood, and milk samples of cows in a typical rural region of Yunnan Province in southwest China, where mixed farming of domestic animals is a common practice. HEV RNA was quantified by quantitative real-time polymerase chain reaction, and the whole genome was sequenced. HEV infectivity was assessed in rhesus macaques. We found a high prevalence of active HEV infection in cows as determined by viral RNA positivity in fecal samples. Surprisingly, we discovered that HEV is excreted into milk that is produced by infected cows. Phylogenetic analysis revealed that all HEV isolates from cow/milk belong to genotype 4 and subtype 4h. Gavage with HEV-contaminated raw and even pasteurized milk resulted in active infection in rhesus macaques. Importantly, a short period of boiling, but not pasteurization, could completely inactivate HEV.

CONCLUSION

Infectious HEV-contaminated cow milk is recognized as a new zoonotic source that bears a high risk of transmission to humans; these results call attention to understanding and establishing proper measurement and control of HEV zoonotic transmission, particularly in the setting of mixed farming of domestic animals. (Hepatology 2016;64:350-359).

New insights into the hepatitis E virus genotype 3 phylodynamics and evolutionary history

Hepatitis E virus (HEV) is an emergent hepatotropic virus endemic mainly in Asia and other developing areas. However, in the last decade it has been increasingly reported in high-income countries. Human infecting HEV strains are currently classified into four genotypes (1-4). Genotype 3 (HEV-3) is the prevalent virus genotype and the mostly associated with autochthonous and sporadic cases of HEV in developed areas. The evolutionary history of HEV worldwide remains largely unknown. In this study we reconstructed the spatiotemporal and population dynamics of HEV-3 at global scale, but with particular emphasis in South America, where case reports have increased dramatically in the last years. To achieve this, we applied a Bayesian coalescent-based approach to a comprehensive data set comprising 97 GenBank HEV-3 sequences for which the location and sampling date was documented. Our phylogenetic analyses suggest that the worldwide genetic diversity of HEV-3 can be grouped into two main Clades (I and II) with a Ƭmrca dated in approximately 320years ago (95% HPD: 420-236years) and that a unique independent introduction of HEV-3 seems to have occurred in Uruguay, where most of the human HEV cases in South America have been described. The phylodynamic inference indicates that the population size of this virus suffered substantial temporal variations after the second half of the 20th century. In this sense and conversely to what is postulated to date, we suggest that the worldwide effective population size of HEV-3 is not decreasing and that frequently sources of error in its estimates stem from assumptions that the analyzed sequences are derived from a single panmictic population. Novel insights on the global population dynamics of HEV are given. Additionally, this work constitutes an attempt to further describe in a Bayesian coalescent framework, the phylodynamics and evolutionary history of HEV-3 in the South American region.

Hepatitis E Virus Genotype 3 in Colombia: Survey in Patients with Clinical Diagnosis of Viral Hepatitis

Background

Hepatitis E virus is a major cause of outbreaks as well as sporadic hepatitis cases worldwide. The epidemiology of this enterically transmitted infection differs between developing and developed countries. The aims of this study were to describe HEV infection in Colombian patients and to characterize the genotype.

Methods

A prospective study was carried out on 40 patients aged over 15 with a clinical diagnosis of viral hepatitis, recruited from five primary health units in the city of Medellin, Colombia. Fecal samples obtained from the 40 consecutives cases were analyzed for HEV RNA using nested reverse transcription PCR for both ORF1 and ORF2-3. The amplicons were sequenced for phylogenetic analyses.

Results

Nine (22.5%) cases of HEV infection were identified in the study population. Three HEV strains obtained from patients were classified as genotype 3. No significant association was found between cases of Hepatitis E and the variables water drinking source, garbage collection system and contact with pigs.

Conclusions

This is the first prospective study of hepatitis E in Colombian patients. The circulation of the genotype 3 in this population is predictable considering the reports of the region and the identification of this genotype from pigs in the state of Antioquia, of which Medellin is the capital. Further studies are necessary to establish whether zoonotic transmission of HEV is important in Colombia.

Epidemiology of Hepatitis E Virus in European Countries

Over the last decade the seroprevalence of immunoglobulin (IgG) anti hepatitis E virus (HEV) has been increasing in European countries and shows significant variability among different geographical areas. In this review, we describe the serological data concerning the general population and risk groups in different European countries. Anti-HEV antibody prevalence ranged from 1.3% (blood donors in Italy) to 52% (blood donors in France). Various studies performed on risk groups in Denmark, Moldova and Sweden revealed that swine farmers have a high seroprevalence of HEV IgG (range 13%-51.1%), confirming that pigs represent an important risk factor in HEV infection in humans. Subtypes 3e,f are the main genotypes detected in the European population. Sporadic cases of autochthonous genotype 4 have been described in Spain, France, and Italy. Although most HEV infections are subclinical, in immune-suppressed and transplant patients they could provoke chronic infection. Fulminant hepatitis has rarely been observed and it was related to genotype 3. Interferon and ribavirin treatment was seen to represent the most promising therapy.

Temporal evolution of the distribution of hepatitis E virus genotypes in Southwestern France

Southwest France is a highly endemic region for hepatitis E virus (HEV). This study examined the circulation of HEV strains between 2003 and 2014 in the Midi-Pyrénées, and compared these data with those from the rest of France. The polyproline region (PPR) of the ORF1 region of the HEV genome was also analyzed. HEV genotype was determined by sequencing a 348-nt fragment within the ORF2 gene for 333 strains in the Midi-Pyrénées and for 571 strains from the rest of France. PPR region was characterized for 56 strains. The frequency of subgenotype 3f decreased over time, whereas subgenotype 3c increased in the Midi-Pyrénées. Repartition of strains did not differ in the Midi-Pyrénées compared to the rest of France. HEV3i and HEV4 have been recently detected throughout France. PPR lengths showed that two major groups of HEV3f exist. Our study shows that HEV3 distribution in the Midi-Pyrénées was similar to the whole of France. Local dietary habits could explain the higher seroprevalence in the Midi-Pyrénées rather the circulation of a particular variant in this region.

First report of hepatitis E virus circulation in domestic pigs in Nigeria

Hepatitis E virus (HEV) is an important cause of acute hepatitis in humans. Zoonotic transmission between pigs and humans has been confirmed. Human HEV infection is common in Nigeria; however, characterization of HEV infection in other species was lacking. The objective of this study was to investigate HEV infection in Nigerian pigs. A total of 286 serum samples from six states in Nigeria were tested for presence of anti-HEV IgG. Ninety fecal samples from one of these states (Plateau State) were tested for presence of HEV RNA. The overall prevalence of anti-HEV IgG-positive or suspect-positive pigs was 55.6% (159 of 286) with regional prevalence rates ranging from 36% (9 of 25; Delta State) to 88% (22 of 25; Taraba State). The overall HEV RNA prevalence rate was 76.7% (69 of 90). All polymerase chain reaction-positive samples belonged to HEV genotype 3 based on sequencing. The results indicate that HEV genotype 3 infection is widespread in Nigerian pigs.

Hepatitis E virus infection

Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries.

Optimization of the elution buffer and concentration method for detecting hepatitis E virus in swine liver using a nested reverse transcription-polymerase chain reaction and real-time reverse transcription-polymerase chain reaction

The aim of this study was to develop an optimal technique for detecting hepatitis E virus (HEV) in swine livers. Here, three elution buffers and two concentration methods were compared with respect to enhancing recovery of HEV from swine liver samples. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and nested RT-PCR were performed to detect HEV RNA. When phosphate-buffered saline (PBS, pH 7.4) was used to concentrate HEV in swine liver samples using ultrafiltration, real-time RT-PCR detected HEV in 6 of the 26 samples. When threonine buffer was used to concentrate HEV using polyethylene glycol (PEG) precipitation and ultrafiltration, real-time RT-PCR detected HEV in 1 and 3 of the 26 samples, respectively. When glycine buffer was used to concentrate HEV using ultrafiltration and PEG precipitation, real-time RT-PCR detected HEV in 1 and 3 samples of the 26 samples, respectively. When nested RT-PCR was used to detect HEV, all samples tested negative regardless of the type of elution buffer or concentration method used. Therefore, the combination of real-time RT-PCR and ultrafiltration with PBS buffer was the most sensitive and reliable method for detecting HEV in swine livers.

Emerging and re-emerging enteric viruses causing multinational foodborne disease outbreaks

ABSTRACT: 

The development of molecular detection methods has led to recognition of viruses as important foodborne pathogens. The most common foodborne virus is norovirus, which together with HAV are transmitted via food consumed raw, such as shellfish, fresh produce and soft fruit. HEV is increasingly being recognized as an emerging foodborne virus in developed countries. The transmission route of HEV includes zoonotic transmission in association with pork products. Ongoing changes in food commerce and production from national to internationally-distributed foodstuffs are leading to widespread infections and multinational outbreaks. Recent large viral outbreaks have been linked to oysters, frozen berries and semidried tomatoes.

Host immune status and response to hepatitis E virus infection

Hepatitis E virus (HEV), identified over 30 years ago, remains a serious threat to life, health, and productivity in developing countries where access to clean water is limited. Recognition that HEV also circulates as a zoonotic and food-borne pathogen in developed countries is more recent. Even without treatment, most cases of HEV-related acute viral hepatitis (with or without jaundice) resolve within 1 to 2 months. However, HEV sometimes leads to acute liver failure, chronic infection, or extrahepatic symptoms. The mechanisms of pathogenesis appear to be substantially immune mediated. This review covers the epidemiology of HEV infection worldwide, the humoral and cellular immune responses to HEV, and the persistence and protection of antibodies produced in response to both natural infection and vaccines. We focus on the contributions of altered immune states (associated with pregnancy, human immunodeficiency virus [HIV], and immunosuppressive agents used in cancer and transplant medicine) to the elevated risks of chronic infection (in immunosuppressed/immunocompromised patients) and acute liver failure and mortality (among pregnant women). We conclude by discussing outstanding questions about the immune response to HEV and interactions with hormones and comorbid conditions. These questions take on heightened importance now that a vaccine is available.

Endemic hepatitis E in the Czech Republic

BACKGROUND

An increasing incidence of endemic hepatitis E (HE) has been reported in developed countries. Thus, an evaluation of the clinical characteristics of the disease and the utility of the current diagnostic methods is warranted.

METHODS

Fifty-one adult acute patients with HE hospitalized in a single center between the years 2009 and 2012 were evaluated. Serological and molecular techniques (detection of hepatitis E virus [HEV] RNA from stool and serum samples by quantitative reverse transcription polymerase chain reaction) with sequencing and phylogenetic analysis were used for diagnosis, and the clinical, laboratory, and epidemiological parameters of the patients were evaluated.

RESULTS

Forty-nine (96.1%) patients had acute endemic HE and 2 (3.9%) had an imported infection. In the cohort of patients with acute symptomatic HE (n = 47), men outnumbered women (40:7), the patients were in older middle age (mean, 60.57 years), and they had elevated median values of total bilirubin (6.67 mg/dL), alanine aminotransferase (2288.82 U/L), aspartate aminotransferase (1251.76 U/L), gamma-glutamyl transferase (360.53 U/L), and alkaline phosphatase (197.06 U/L). Serology was positive in 50 (98%) of the patients, and 1 case was diagnosed by polymerase chain reaction only. HEV RNA was detected in at least 1 specimen from 84.3% of the patients, and 28 of 29 tested isolates belonged to genotype 3. The eating of meat, innards, other home-prepared pork products, or the tasting of raw meat before cooking were the most frequently reported data (reported by 25 patients [49.0%]).

CONCLUSIONS

Large numbers of the endemic cases of HE were caused by HEV genotype 3, and the clinical characteristics of endemic HE were demonstrated.

Evaluation of hepatitis E virus infection between different production systems of pigs in Brazil

The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n = 5) or family-scale farms (n = 5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.

Emergence of autochthonous infections with hepatitis E virus of genotype 4 in Europe

In Europe, autochthonous hepatitis E is caused by genotype 3 hepatitis E virus (HEV) in almost all cases. A total of 15 infections with genotype 4 HEV were diagnosed in France from May 2009 to April 2012, and all but one of the HEV-4 strains implicated in these infections were genetically related and highly similar to HEV-4 sequences isolated from swine in Belgium. In addition, 5 autochthonous HEV-4 infections have been described in the region of Lazio, Italy, during March and April 2011, and these HEV sequences were 100% identical to one another but showed relatively low similarity (74-85%) to HEV-4 RNA samples collected in France. We report 6 additional HEV-4 infections that were diagnosed from May to July 2012 which represented 50% of the HEV infections diagnosed during this period in our clinical microbiology laboratory. Five of these HEV-4 strains were associated with autochthonous infections and were clustered together and with the majority of HEV-4 previously described in France, whereas the sixth strain was genetically divergent. Taken together with reports from other teams, these observations indicate that autochthonous infections with HEV-4 are emerging in Europe and have been transmitted by at least two distinct sources.

Genotype-4 hepatitis E in a human after ingesting roe deer meat in South Korea

The recent increase in the number of cases of indigenous hepatitis E virus (HEV) infection highlights the importance of identifying the transmission routes for the prevention of such infections. Presented herein is the first case of acute HEV infection after ingesting wild roe deer meat in South Korea. A 43-year-old male presented with abdominal discomfort and jaundice. He had not recently traveled abroad, but had eaten raw roe-deer meat 6-8 weeks before the presentation. On the 7th day of hospitalization the patient was diagnosed with acute viral hepatitis E. Phylogenetic analysis of his serum revealed genotype-4 HEV. This case supports the possibility of zoonotic transmission of HEV because the patient appears to have been infected with genotype-4 HEV after ingesting raw deer meat.

Hepatitis E virus infection in Latin America: a review

Data reported during recent years reveal the complex picture of the epidemiology of hepatitis E virus (HEV) infection in Latin America. Whereas in countries like Argentina and Brazil is almost identical to the characteristic of most countries from North America and Europe, HEV in the Caribbean and Mexico involves the water-borne, non-zoonotic viral genotypes responsible for epidemics in Asia and Africa. Nevertheless, Latin America has been considered a highly endemic region for hepatitis E in the scientific literature, a generalization that ignores the above complexity. In addition, reports from isolated Amerindian communities, which display well known, important and very specific epidemiological features for hepatitis B and D virus infections are neither taken into account when considering the epidemiology of hepatitis E in the region. This review updates compilation of the available information for the HEV infection, both among humans and other mammals, in Latin America, discusses the strengths and the weaknesses of our current knowledge, and identifies future areas of research.

Hepatitis E virus seroprevalence and risk factors for individuals in working contact with animals

BACKGROUND

In industrial countries genotypes 3 and 4 of HEV are detected in swine, wild boar, deer and rabbits, and they are associated with autochthonous infections suggesting the existence of zoonotic HEV infections, compatible with the putative involvement of undercooked pork and big game products as a source of infection.

OBJECTIVES

To evaluate the prevalence of anti-HEV antibodies in different population groups in contact with animals and to investigate risk factors for HEV infection.

STUDY DESIGN

Serum samples were collected from 859 healthy French subjects, including pig farm workers, forestry workers and individuals without working contact with animals (control group). In addition, 58 swine veterinarians were included in the study. Subjects were interviewed using a structured questionnaire, and anti-HEV antibodies were investigated using a sensitive and specific sandwich ELISA.

RESULTS

Anti-Hepatitis E virus (HEV) antibodies were detected in 26% of control population, and in 36% and 44% of forestry and pig farm workers, respectively. In addition, an increase in seroprevalence from the north to the south of France was observed (30.2% versus 40.7%). Consumption of pork liver sausage (AOR 4.4, p < 10(-4)), occupational contact with animals (AOR 1.58, p = 0.038 for forestry workers and AOR 2.51, p < 10(-4) for pig farm workers), and living in southern France (AOR 1.47, p = 0.02), were independent risk factors. Wearing working gloves and boots might reduce HEV infection.

CONCLUSIONS

Occupational exposure to animals and consuming raw or undercooked pork liver sausage or pork liver play a significant role in HEV transmission in industrial countries.

Development of a fluorescent microbead-based immunoassay for the detection of hepatitis E virus IgG antibodies in pigs and comparison to an enzyme-linked immunoassay

Swine hepatitis E virus (HEV) is a zoonotic virus and pigs are considered as an important reservoir. Swine HEV infection is widespread and most pig herds are infected. Humans can be infected with swine HEV via consumption of undercooked pork or through direct contact with infected pigs. To minimize the risk of zoonotic transmission, sensitive tools to assess the HEV infection status of pigs and pork products are needed. The objective of this study was to develop a fluorescent microbead-based immunoassay (FMIA) for the detection of IgG antibodies against swine HEV and compare it to an in-house enzyme-linked immunoassay (ELISA). Three sets of samples were utilized: (A) samples from pigs infected experimentally with different strains of HEV (positive controls, n=72), (B) samples from known HEV-negative pigs (negative controls, n=62) and (C) samples from pigs of unknown HEV infection status (n=182). All samples were tested by both ELISA and FMIA. The results on the experimental samples with known HEV exposure indicate that both assays have a specificity of 100% while the sensitivity ranges from 84.6% (ELISA) to 92.3% (FMIA). The overall prevalence of HEV IgG antibodies in field samples from pigs with unknown HEV exposure was 21.9% (40/182) for the ELISA and 21.4% (39/182) for the FMIA. The two assays had an almost perfect overall agreement (Kappa=0.92).

Hepatitis E virus genotype 4 outbreak, Italy, 2011

During 2011, 5 persons in the area of Lazio, Italy were infected with a monophyletic strain of hepatitis E virus that showed high sequence homology with isolates from swine in China. Detection of this genotype in Italy parallels findings in other countries in Europe, signaling the possible spread of strains new to Western countries.

Genotype 4 hepatitis e virus in france: an autochthonous infection with a more severe presentation

Among hepatitis E virus (HEV) infections diagnosed in 2011 by the French Reference Centre for HEV, 9 were due to genotype 4, which until recently was limited to Asia. Sequences from autochthonous cases formed a single cluster very similar to Belgian swine sequences. Clinical presentation differed from genotype 3 infections.

Chronic hepatitis E infection: risks and controls

Very recently, an unusual clinical presentation with an altered natural history associated with hepatitis E virus (HEV) infection has emerged in high-income industrialized nations. Although HEV infection does not develop into chronicity in general, viremia can persist for long periods of time in immunocompromised solid organ, bone marrow and stem cell transplant patients. Conceivably, the atypical clinical and virological outcomes in these cases could be related to immunosuppressive chemotherapy, resulting in suboptimal HEV-specific immune responses. In the absence of travel to endemic regions, foodborne autochthonous HEV infection due to viral genotypes 3 and 4 has been implicated in the chronic cases. Presently, pegIFN-α-2a and ribavirin, the commonly used drugs to treat chronic viral hepatitis, are proving very promising in hepatitis E patients. Nevertheless, the most-awaited HEV vaccine could be protective in naïve travelers or high-risk group populations. The mechanisms of establishing chronic HEV infection and the disease severity have hitherto not been clearly understood. Therefore, a comprehensive clinical, virological and molecular study is needed to understand and control the disease.

Hepatitis E virus genotype 4 isolated from a patient with liver failure: full-length sequence analysis showing potential determinants of virus pathogenesis

The full-length genome sequence of a genotype 4 strain of Hepatitis E virus (HEV) (CHN-NJ-H2011) from a patient (in Nanjing, China) with liver failure has been determined. Phylogenetic analysis showed that CHN-NJ-H2011 belongs to genotype 4, subtype 4h. Comparative sequence analysis carried out on a 301-bp fragment of ORF2 showed that CHN-NJ-H2011 shares high nucleotide sequence identity (94.3-94.7 %) with porcine viruses (ch-shsw1 and Ch-estw2) isolated in the same geographical region, pointing to the strong possibility of zoonotic transmission of HEV genotype 4. A broader comparison with other genotype 4 isolates revealed 12 unique amino acid substitutions in ORF1 and three in ORF2 that might serve as signatures of disease severity for genotype 4 HEV infection.

High hepatitis E virus seroprevalence in forestry workers and in wild boars in France

Hepatitis E virus (HEV) is a fecally and orally transmitted human pathogen of worldwide distribution. In industrial countries, HEV is observed in an increasing number of autochthonous cases and is considered to be an emerging pathogen. A growing body of evidence suggests that HEV is a zoonotic disease, and pig handlers and pig veterinarians have been reported to be high-risk groups for HEV infection. The aims of the present study were to establish the prevalence of anti-HEV in wild boars in France and to identify whether forestry workers are at a higher risk of HEV infection. Three different anti-HEV tests were used to compare their effectiveness in detecting anti-HEV in the general population. The most sensitive test was then used to investigate HEV seroprevalence in 593 forestry workers and 421 wild boars. Anti-HEV was detected in 31% of the forestry workers and 14% of the wild boars. Detection of anti-HEV in humans was correlated with age, geographical location, and occupational activity and in wild boars was correlated with geographical location. HEV infection is frequent in woodcutters in France, and it varies geographically. Further studies are needed to confirm these findings and to elucidate the transmission route and the exact virus reservoirs.