Evaluation of novel synthetic peptides of avian hepatitis E virus ORF2 as vaccine candidate in chickens.

Avian hepatitis E virus (HEV) has resulted in significant economic losses in the poultry industry. There is currently no commercial vaccination available to prevent avian HEV infection. Previously, a novel epitope (601TFPS604) was discovered in the ORF2 protein of avian HEV. In this study, peptides were synthesized and assessed for their ability to provide immunoprotecting against avian HEV infection in poultry. Twenty-five Hy-Line Variety Brown laying hens were randomly divided into five groups; groups 1 to 3 respectively immunized with RLLDRLSRTFPS, PETRRLLDRLSR (irrelevant peptide control), or truncated avian HEV ORF2 protein (aa 339-606), while group 4 (negative control) was mock-immunized with PBS and group 5 (normal control) was not immunized or challenged. After the challenge, all hens in groups 2 and 4 showed seroconversion, fecal virus shedding, viremia, alanine aminotransferase (ALT) level increasing, liver lesions and HEV antigen in the liver. There were no pathogenic effects in other groups. Collectively, all of these findings showed that hens were completely protected against avian HEV infection when they were immunized with the peptide containing TFPS of the avian HEV ORF2 protein.

The 2023 South Sudanese outbreak of Hepatitis E emphasizes ongoing circulation of genotype 1 in North, Central, and East Africa.

In April 2023, an outbreak of acute hepatitis was reported amongst internally displaced persons in the Nazareth community of South Sudan. IgM serology-based screening suggested the likely etiologic agent to be Hepatitis E virus (HEV). In this study, plasma specimens collected from anti-HEV IgM-positive cases were subjected to additional RT-qPCR testing and sequencing of extracted nucleic acids, resulting in the recovery of five full and eight partial HEV genomes. Maximum likelihood phylogenetic reconstruction confirmed the genomes belong to HEV genotype 1. Using distance-based methods, we show that genotype 1 is best split into three sub-genotypes instead of the previously proposed seven, and that these sub-genotypes are geographically restricted. The South Sudanese sequences confidently cluster within sub-genotype 1e, endemic to northeast, central, and east Africa. Bayesian Inference of phylogeny incorporating sampling dates shows that this new outbreak is not directly descended from other recent local outbreaks for which sequence data is available. However, the analysis suggests that sub-genotype 1e has been consistently and cryptically circulating locally for at least the past half century and that the known outbreaks are often not directly descended from one another. The ongoing presence of HEV, combined with poor sanitation and hygiene in the conflict-affected areas in the region, place vulnerable populations at risk for infection and its more serious effects, including progression to fulminant hepatitis.

Seroprevalence of swine hepatitis E virus and the farmers' potential risk of infection in the Province of Bali, Indonesia.

Background and Aims: Hepatitis E virus (HEV) infection formerly and predominantly occurred in rural areas. However, it has recently been spread to urban and peri-urban areas. This study aimed to estimate the seroprevalence of HEV in pigs collected from urban and rural areas in Bali. The potential of the pig farmers' risk level for being exposed to HEV and the virus transmitted to them in association with their pig-rearing practices was also assessed. Materials and Methods: A total of 183 pigs from 68 herds were sampled in this study, with 91 pigs collected from Denpasar as the representative samples of urban areas and 92 pigs from Karangasem Regency as the representative samples from rural areas. Sera from the sampled pigs were collected and immunoglobulin G antibodies against HEV were detected using a commercial enzyme-linked immunosorbent assay. A questionnaire was prepared for interviewing the farmers. Bivariable and multivariable logistic regression analyses were performed to identify the putative factors associated with seropositivity. Meanwhile, the potential risk-incurring practices of the farmers for HEV being transmitted to them from their pig-rearing practices were assessed by scoring their responses from the interview. Results: Overall, 23.5% (43/183) (95% confidence interval [CI]: 17.6-30.3) pig sera tested were detected to have the antibodies against HEV. Among 68 pig herds, 36.8% (25) (95% CI: 25.4-49.3) of them had antibodies in at least one pig sampled from each herd. Pigs sampled from Karangasem were 5 times (Odds ratio [OR] 5.34, 95% CI: 2.27-13.54, p < 0.001) more likely to be seropositive than pigs collected from Denpasar. However, no difference was found in the seropositivity to HEV in pig herds between Denpasar and Karangasem (p = 0.05). In assessing the pig rearing management factors, pig farmers from Denpasar were 3 times (OR 3.0, 95% CI: 1.07-8.52, p = 0.05) more likely to rear pigs for economic investment compared to the farmers from Karangasem. Regarding anticipating pig diseases that can be transmitted to humans, farmers from Denpasar were 6 times (OR 5.72, 95% CI: 1.48-26.7, p = 0.0074) more likely to anticipate zoonotic diseases compared to the farmers from Karangasem. Similarly, pig farmers from Denpasar were 3 times (OR 3.29, 95% CI: 1.08-10.23, p = 0.035) more likely to anticipate pig diseases that could be transmitted to humans than the farmers from Karangasem. Pig farmers from Denpasar had 4 times the odds (OR 4.49, 95% CI: 1.11-18.19, p = 0.03) of washing their hands after going to the pigpens compared to the farmers from Karangasem. All the participants were categorized as being at high risk of HEV exposure and transmission. Conclusion: IgG antibodies against HEV were detected among pigs reared in rural areas of Karangasem and those reared in urban areas of Denpasar. This suggests that the risk of HEV exposure and transmission in these areas is not negligible. To minimize the risk, public education on zoonotic diseases, including HEV infection, transmission, and prevention, needs to be implemented and particularly targeted to local pig farmers.

Successful recovery from acute-on-chronic liver failure due to acute hepatitis E virus superinfection in chronic hepatitis B: A case report.

Introduction: Acute hepatitis E virus (HEV) infection is a self-limiting disease, but HEV superinfection in patients with chronic hepatitis B virus (HBV) infection may lead to acute-on-chronic liver failure (ACLF) and significantly increase short-term mortality. Diagnosis and comprehensive management of these patients remain in a dilemma. Case presentation: A 32-year-old man with chronic HBV infection for 8 years received entecavir due to abnormal liver function for 4 months. He was admitted for symptomatic hepatitis flare for nearly 2 weeks. Initial investigations did not reveal a cause other than HBV, but repeated tests showed a progressive increase in his anti-HEV IgM. His condition worsened rapidly. Mid-stage ACLF and spontaneous peritonitis were diagnosed. Entecavir and hepatoprotective drugs were continued. Ribavirin, ceftriaxone, and repeated artificial liver support system (ALSS) therapy were administered. His condition gradually improved and his liver function eventually returned to normal. Conclusions: Repeated HEV screening is important for patients with chronic liver disease and symptomatic hepatitis flare. Negative anti-HEV IgM for the first time can easily lead clinicians to mistakenly rule out HEV infection. A progressive increase in anti-HEV IgM is one of the diagnostic criteria for HEV infection, which is not rare but deserves attention. Additionally, comprehensive management including ribavirin and ALSS would be effective therapies for patients who superinfect with HEV and develop ACLF.

HEV-3 subtypes and strains detected in cases of HEV infection in central Italy from 2015 to 2023.

PURPOSE: HEV is an emerging pathogen in Europe and was previously shown to be hyperendemic in areas of Abruzzo and Lazio, Central Italy. No systematic analysis of the HEV strains responsible for human infections over several years in Central Italy has previously been reported. Aim of the study was the molecular characterization of HEV from autochthonous hepatitis E cases occurred in Abruzzo and Lazio between 2015 and 2023. METHODS: Samples from 118 cases collected as part of virological surveillance in Abruzzo and Lazio from 2015 to 2023 were subjected to HEV sequencing and phylogenetic analysis. RESULTS: The main observed subtype was 3f, followed by 3c and 3e. The annual subtype distribution was quite stable over the observation period, but 3f cases tended to concentrate in winter/early spring whereas 3e cases in summer. Phylogenetic clusters of highly related sequences (a) highlighted unrecognized "point source outbreaks", (b) provided molecular support to temporally and/or geographically linked cases and (c) provided evidence for transmission of identical/highly related strains up to months/years following their first detection. CONCLUSIONS: The data provide an overview of the HEV strains responsible for human infections over eight years in Central Italy. The observed subtype distribution appears to agree better with the subtype distribution reported in Italy in pigs rather than in geographically matched wild boars, suggesting pig and its derivate food was a more frequent source of infection than wild boar in Abruzzo and Lazio. Molecular characterization is essential to recognize "point source outbreaks" and to monitor HEV circulation.

Global temporal trends and projections of acute hepatitis E incidence among women of childbearing age: Age-period-cohort analysis 2021.

BACKGROUND & AIMS: Acute hepatitis E (AHE) poses a significant threat to global public health, particularly among women of childbearing age (WCBA), who are at heightened risk for severe pregnancy-related complications. This study aimed to delineate the temporal trends and project future incidence of AHE in WCBA, providing insights crucial for targeted prevention and control strategies. METHODS: Data on AHE incidence from the Global Health data 2021. The age-period-cohort (APC) model was applied to analyze trends across different age groups, periods, and birth cohorts, and the Bayesian APC model was utilized for forecasting future epidemiological trajectories. RESULTS: Globally, AHE incidence numbers among WCBA rose from 2,831,075 in 1992 to 3,420,786 in 2021, while the age-standardized incidence rate (ASIR) declined from 194.66 to 179.54 per 100,000 with a global net drift of -0.28%. However, high SDI regions showed a contrasting trend with a positive net drift of 0.02%. The age effect was consistent across SDI regions and globally, showing a decrease with advancing age, while unfavorable period and cohort effects were exhibited in high-SDI region. At the national level, locations exhibited varying trends of change. The BAPC model predicted a total of 3,759,384 AHE global cases in WCBA by 2030, with an expected mild increase in the ASIR. The outlook for the management and containment of AHE is grim in certain countries, including India. CONCLUSIONS: The study revealed a complex epidemiological landscape of AHE in WCBA, with increasing global incidence numbers juxtaposed against a declining ASIR. The AHE burden by 2030 remain severe among WCBA. Young WCBA and high SDI region merit particular attention. The findings underscore the need for region-specific strategies to curb the projected rise in AHE incidence and align with the 2030 WHO goals.

Prevalence and Incidence of Hepatitis E Infection in China.

BACKGROUND AND AIMS: China is an endemic area for hepatitis E virus (HEV) infection. Estimating the prevalence and incidence of HEV infection in China plays a pivotal role in informing public health policies to prevent and control hepatitis E. This study aimed to investigate the prevalence of anti-HEV IgG and incidence of HEV seroconversion in China. METHODS: This study was based on the Meinian health check-up database in China. Participants who underwent testing for anti-HEV IgG at check-up centers in 24 provinces between 2017 and 2022 were included. In the cross-sectional analyses, overall prevalence and stratified prevalence in subpopulations with various characteristics were estimated and standardized according to the 2020 census of the Chinese population. In the longitudinal analyses, the occurrence of anti-HEV IgG positivity during the follow-up was defined as an incident HEV seroconversion. Overall and stratified incidence rates were estimated and expressed as per 100 person-years. Poisson regression was used to explore risk factors associated with HEV seroconversion. RESULTS: A total of 85,238 and 11,154 participants were included in the cross-sectional and longitudinal analyses, respectively. The prevalence of anti-HEV IgG in the general population was 18.02%. During a median follow-up of 1.2 years, the incidence rate of HEV seroconversion was 1.79 per 100 person-years. Age ≥60 years, low socioeconomic status, living in coastal areas, living in areas with high drainage density, and living in areas with high anti-HEV IgG prevalence were independent risk factors for HEV seroconversion. CONCLUSIONS: Our findings would help inform policymaking for hepatitis E prevention and control in China as well as in other endemic regions of the world.

Understanding hepatitis E vaccination intention among women of childbearing-age: A theory-based cross-sectional study.

OBJECTIVES: The purpose of this study was to investigate the HEV vaccination intention, its determinants, and overall influence mechanisms among childbearing-age women. METHOD: The current study was cross-sectional and conducted online from June 25, 2023 to September 25, 2023 in Nanjing, China. Logistic regression models were constructed to identify the intention-associated background factors. Technology Acceptance Model (TAM) and Theory of Planned Behavior (TPB) were integrated and expanded as TAM-TPB model to further investigate the determinants and overall influence mechanism of HEV vaccination intention among this population using structural equation modeling. RESULTS: A total of 423 eligible participants were included in this study. High general HEV knowledge was independently associated with an increased intention to get HEV vaccination (OR = 1.97, 95 % CI: 1.11-3.58, P = 0.023). All the hypotheses proposed in the theoretical TAM-TPB model were supported, with perceived ease of use, perceived usefulness, attitude, subjective norm, and perceived behavioral control positively affecting the intention of HEV vaccination (all P values <0.05), while perceived risk (P = 0.003) exhibited an inverse association with HEV vaccination intention. The model achieved an acceptable fit, and the total explained variance of HEV vaccination intention was as high as 86.20 %. Moreover, no significant common method bias was observed. CONCLUSION: This is the first theory-based study that explored the HEV vaccination intention, its determinants, and overall influence mechanism among childbearing-age women. The results of the current study are of great importance for improving the understanding of the HEV vaccination intention among females of childbearing age.

Prevalence of hepatitis A and E viruses in wastewater in Asian countries.

Hepatitis A and E viruses (HAV and HEV, respectively) remain a significant global health concern despite advancements in healthcare and vaccination programs. Regular monitoring and vaccine efficacy of HAV are still lacking in different countries. This study aimed to investigate HAV and HEV prevalence in developed, developing, and least-developed Asian countries using wastewater as a surveillance tool. A total of 232 untreated wastewater samples were collected from six wastewater treatment plants, a sewage treatment plant, or an open drainage in six countries [Nepal (n = 51), Indonesia (n = 37), Thailand (n = 30), Vietnam (n = 27), the Philippines (n = 17), and Japan (n = 70)] between April and October 2022. Viruses in wastewater were concentrated by simple centrifugation or polyethylene glycol precipitation method, followed by viral RNA extraction and reverse transcription-quantitative polymerase chain reaction. HAV and HEV RNA were detected in the samples from Nepal (51 % for HAV and 2 % for HEV), Thailand (3 % for both viruses), and Japan (1 % for HAV and 24 % for HEV). Only HAV RNA was found in 11 % of the samples in Indonesia, whereas only HEV RNA was detected in Vietnam and the Philippines, with a positive ratio of 15 % and 12 %, respectively. These results highlighted the geographic variability in HAV and HEV prevalence, underscoring the need for localized public health strategies to address specific viral hepatitis challenges in each country.

Serological indication of chronic inflammatory demyelinating polyneuropathy as an extrahepatic manifestation of hepatitis E virus infection.

Guillain-Barré syndrome and neuralgic amyotrophy have been associated with hepatitis E virus (HEV) genotype 3 infections, while myasthenia gravis (MG) has been associated with HEV genotype 4 infections. However, whether chronic inflammatory demyelinating polyneuropathy (CIDP) is associated with HEV infections has not been conclusively clarified yet. 102 CIDP patients, 102 age- and sex-matched blood donors, 61 peripheral neuropathy patients (non-CIDP patients), and 26 MG patients were tested for HEV and anti-HEV IgM and IgG. Sixty-five of the 102 (64%) CIDP patients tested positive for anti-HEV IgG and one (1%) for anti-HEV IgM. No other patient tested positive for ati-HEV IgM. In the subgroup of CIDP patients with initial diagnosis (without previous IVIG treatment), 30/54 (56%) tested positive for anti-HEV IgG. Anti-HEV rates were significantly lower in blood donors (28%), non-CIDP peripheral neuropathy patients (20%), and MG patients (12%). No subject tested positive for HEV viremia. CSF tested negative for in 61 CIDP patients (54 patients with primary diagnosis). The development of CIDP but not non-CIDP polyneuropathy may be triggered by HEV exposure in an HEV genotype 3 endemic region. The increased anti-HEV seroprevalence in CIDP patients is not a consequence of IVIG therapy.

Systematic Evaluation of Guidelines for the Diagnosis and Treatment of Hepatitis E Virus Infection.

Background and Aims: The hepatitis E virus (HEV) is a zoonotic disease, and infection with HEV in humans primarily causes acute infections and can progress to chronic manifestation in immunocompromised individuals. Over the past decade, guidelines for diagnosing and treating HEV infection have been developed. This study aimed to systematically assess the quality of current guidelines for diagnosing and treating HEV infection, and we analyzed the differences in guideline quality and primary recommendations and explored possible reasons for these differences. Methods: Guidelines published between 2013 and 2022 were searched, and studies were identified using selection criteria. The study assessed the quality of the included guidelines using the Appraisal of Guidelines for Research and Evaluation tool, extracted the primary recommendations in the guidelines, determined the highest level of evidence supporting the recommendations, and reclassified the evidence using the Oxford Centre for Evidence-Based Medicine grading system. Results: Seven guidelines were included in the final analysis. The quality of the guidelines varied widely. The discrepancies may have been caused by the lack of external experts, the failure to consider influencing factors in guideline application, and the lack of consideration of the public's opinion. Analysis of the heterogeneity in primary recommendations revealed differences in algorithms for managing chronic HEV infection, the dosage of ribavirin, and a low level of evidence supporting the primary recommendations. Conclusions: Guideline quality and primary recommendations vary considerably. Refinement by guideline developers and researchers would facilitate updating and applying guidelines for diagnosing and treating HEV infection.

NLRP3 Inflammasome Activation Mediates Hepatitis E Virus-Induced Neuroinflammation.

Hepatitis E virus (HEV) is a foodborne zoonotic pathogen that is supposed to be one of the most common causes of acute viral hepatitis. However, HEV infection has been recently associated with a wide spectrum of extrahepatic manifestations, particularly neurological disorders. Previous studies have shown that HEV is able to cross the blood-brain barrier (BBB) and induce inflammatory response of the central nervous system. However, the pathogenesis of HEV-induced neuroinflammation and tissue injury of the central nervous system have yet to be fully elucidated. In this study, activation of NLRP3 inflammasome following HEV infection were investigated. In a gerbil model infected by HEV, brain histopathological changes including gliosis, neuronophagia and neuron injury were observed and expression of NLRP3, caspase-1, IL-1ß and IL-18 were elevated. Brain microvascular endothelial cells (BMECs) are key components of the BBB that protects the brain from various challenges. Following HEV infection, virus-like particles range from 30 to 40 nm in diameter were observed in human BMECs (hBMECs). Enhanced expression levels of NLRP3 and subsequent ASC, caspase-1, IL-1ß and IL-18 were detected in infected cells. Treatment with MCC950 alleviated HEV infection induced activation of NLRP3 inflammasome, mitochondrial damage and VE-cadherin degradation. The findings provide new insights into HEV-associated neuroinflammation. Moreover, targeting NLRP3 inflammasome signalling is a promising therapeutic in HEV-induced neurological disorder.

Epidemiology and Outcomes of Hepatitis E Virus-Associated Hospitalisations in the United States With a Focus on Pregnancy: A Nationwide Population Study, 1998-2020.

Hepatitis E virus (HEV) is typically asymptomatic in developed countries but can be more severe in certain populations. We aim to describe the epidemiology of HEV-associated hospitalisations from 1998 to 2020 in the United States, investigate risk factors for inpatient mortality and describe outcomes in pregnant women. We utilised the National Inpatient Sample and extracted cases of HEV-associated hospitalisations using ICD-9/10 diagnostic codes. Demographic, clinical and pregnancy data were extracted and analysed by chi-square and logistic regression. We identified 3354 cases of HEV-associated hospitalisations; 1689 (50.4%) were female and 1425 (42.5%) were non-Hispanic White. The median age was 50 (IQR: 37-59) years. Hospitalisation rates for HEV ranged from 2.5 per 10,000,000 in 2008 to a peak of 9.6 per 10,000,000 people in the general U.S. population in 2004. The mortality rate was 5.2%. Age ≥ 40 years (OR: 7.73; 95% CI: 1.57-38.09; p = 0.012), HIV infection (OR: 4.63; 95% CI: 1.26-16.97; p = 0.021), and coagulopathy (OR: 7.22; 95% CI: 2.81-18.57; p < 0.001) were associated with increased odds of mortality within the HEV cohort. There were 226 pregnant women with HEV. Rates of maternal death, stillbirth and preterm birth were similar between HEV and non-HEV pregnant cohorts. Hepatitis B and hepatitis C co-infection were significantly more common in the HEV pregnant cohort (p < 0.05). HEV-associated hospitalisations are uncommon in the United States, but likely underdiagnosed. Certain risk factors can be used to predict prognosis of these hospitalised patients. Pregnant women with HEV appear to have favourable maternal and fetal outcomes despite hepatitis B and C co-infection.

Acute hepatitis E virus infection presenting as meningo-encephalitis.

BACKGROUND: Acute hepatitis E infection (HEV), with its high incidence in Europe, should be considered as a differential diagnosis of acute viral hepatitis and can in some cases manifest with pronounced neurological symptoms. CLINICAL CASE: We report on a 33-year-old female patient with severe arthralgia, myalgia, headache and psychomotor deterioration. Laboratory analyses showed elevated transaminases without signs of cholestasis. Acute hepatitis E virus infection was detected in serum. She reported fatigue and dysesthesias not responsive to analgesics. Cerebrospinal fluid (CSF) analysis revealed an inflammatory syndrome. HEV RNA was detected in the CSF. The infection remained mild, but dysesthesias persisted. Eight weeks after the first admission, the symptoms worsened again. Complete and sustained remission was achieved following intravenous corticosteroid treatment. CONCLUSION: In patients with acute neurological symptoms and liver enzyme elevation, HEV infection should be considered. Neurologic symptoms such as fatigue, arthralgia, myalgia and dysesthesia along with psychomotor retardation should prompt CSF analysis.

Investigating the Hepatitis E Virus (HEV) Diversity in Rat Reservoirs from Northern Italy.

Hepatitis E virus belonging to the Rocahepevirus ratti species, genotype HEV-C1, has been extensively reported in rats in Europe, Asia and North America. Recently, human cases of hepatitis associated with HEV-C1 infection have been reported, but the zoonotic nature of rat-HEV remains controversial. The transmission route of rat-HEV is unidentified and requires further investigation. The HEV strains of the Paslahepevirus balayani species, belonging to the same Hepeviridae family, and including the zoonotic genotype HEV-3 usually found in pigs, have also sporadically been identified in rats. We sampled 115 rats (liver, lung, feces) between 2020 and 2023 in Northeast Italy and the HEV detection was carried out by using Reverse Transcription PCR. HEV RNA was detected in 3/115 (2.6%) rats who tested positive for HEV-C1 strains in paired lung, intestinal contents and liver samples. Overall, none tested positive for the Paslahepevirus balayani strains. In conclusion, our results confirm the presence of HEV-rat in Italy with a prevalence similar to previous studies but show that there is a wide heterogeneity of strains in circulation. The detection of HEV-C1 genotype of Rocahepevirus ratti species in some human cases of acute hepatitis suggests that HEV-C1 may be an underestimated source of human infections. This finding, with the geographically widespread detection of HEV-C1 in rats, raises questions about the role of rats as hosts for both HEV-C1 and HEV-3 and the possibility of zoonotic transmission.

Serological and molecular survey of rat hepatitis E virus (Rocahepevirus ratti) in drug users.

ABSTRACTRat hepatitis E virus (ratHEV) is an emerging cause of acute hepatitis of zoonotic origin. Since seroprevalence studies are scarce, at-risk groups are almost unknown. Because blood-borne infections frequently occur in people with drug use, who are particularly vulnerable to infection due to lack of housing and homelessness, this population constitutes a priority in which ratHEV infection should be evaluated. Therefore, the aim of this study was to evaluate the ratHEV seroprevalence and RNA detection rate in drug users as a potential at-risk population. We designed a retrospective study involving individuals that attended drug rehabilitation centres. Exposure to ratHEV was assessed by specific antibody detection using ELISA and dot blot (DB) assay and the presence of active infection by ratHEV RNA detection using RT-qPCR. Three-hundred and forty-one individuals were included, the most of them being men (67.7%) with an average age of 45 years. A total of 17 individuals showed specific IgG antibodies against ratHEV (4.6%; 95% CI; 3.1%-7.9%). One case of active ratHEV infection was identified (0.3%; 95% CI: 0.1%-1.8%). This was a 57-year-old homeless woman with limited financial resources, who had active cocaine and heroin use via parenteral route. In conclusion, we identified a potential exposure to ratHEV among drug users. Targeted studies in drug users with proper control groups are necessary to evaluate high-risk populations and transmission routes more accurately.

Realm of hepatitis E: Challenges and opportunities.

Hepatitis E virus (HEV), responsible for widespread viral hepatitis, infects approximately 2.3 billion individuals globally, with a significant mortality burden in Asia. The virus, primarily transmitted through contaminated water and undercooked meat, is often underdiagnosed, particularly in immunocompromised patients. Current HEV treatments, while effective, are limited by adverse effects, necessitating research into safer alternatives. Moreover, HEV's extrahepatic manifestations, impacting the nervous and renal systems, remain poorly understood. This study underscores the imperative for enhanced HEV research, improved diagnostic methods, and more effective treatments, coupled with increased public health awareness and preventive strategies.

Near full-length genome analysis of HEV 4b subtype in pigs showed a similarity up to 99.944% compared to a patient in Guangdong province, China.

Hepatitis E virus (HEV) is a prevalent pathogen responsible for acute viral hepatitis, HEV genotypes 3 and 4 infections causing zoonotic infections. Currently, the nucleotide similarity analysis between humans and pigs for HEV genotype 4 is limited. In this study, stool samples from an HEV-infected patient who is a pig farmer and from pigs were collected to obtain the near full-length genome of HEV, phylogenetic trees were constructed for genotyping, and similarity of HEV sequences was analyzed. The results showed that HEV-RNA was detected in the stool samples from the patient and six pigs (6/30, 20.0%). Both HEV subtype in the patient and pigs was 4b. Additionally, similarity analysis showed that the range was 99.875%-99.944% between the patient and pigs at the nucleotide level. Four isolates of amino acid sequences (ORFs 1-3) from pigs were 100% identical to the patient. Phylogenetic tree and similarity analysis of an additional nine HEV sequences isolated from other patients in this region showed that the HEV sequence from the pig farmer had the closest relationship with the pigs from his farm rather than other sources of infection in this region. This study provides indirect evidences for HEV subtype 4b can be transmitted from pigs to humans at the nucleotide level. Further research is needed to explore the characteristics of different HEV subtypes.

Rat hepatitis E virus cross-species infection and transmission in pigs.

Strains of Rocahepevirus ratti, an emerging hepatitis E virus (HEV), have recently been found to be infectious to humans. Rats are a primary reservoir of the virus; thus, it is referred to as "rat HEV". Rats are often found on swine farms in close contact with pigs. Our goal was to determine whether swine may serve as a transmission host for zoonotic rat HEV by characterizing an infectious cDNA clone of a zoonotic rat HEV, strain LCK-3110, in vitro and in vivo. RNA transcripts of LCK-3110 were constructed and assessed for their replicative capacity in cell culture and in gnotobiotic pigs. Fecal suspension from rat HEV-positive gnotobiotic pigs was inoculated into conventional pigs co-housed with naïve pigs. Our results demonstrated that capped RNA transcripts of LCK-3110 rat HEV replicated in vitro and successfully infected conventional pigs that transmit the virus to co-housed animals. The infectious clone of rat HEV may afford an opportunity to study the genetic mechanisms of rat HEV cross-species infection and tissue tropism.

Corrigendum: Biosecurity measures to control hepatitis E virus on European pig farms.

[This corrects the article DOI: 10.3389/fvets.2024.1328284.].