Chronic hepatitis E: Advancing research and patient care

Macrophage-augmented organoids recapitulate the complex pathophysiology of viral diseases and enable development of multitarget therapeutics

The pathophysiology of acute viral diseases is complex. It is characterized by strong inflammatory responses driven by immune cells, leading to tissue damage. Currently available in vitro models mainly recapitulate the viral life cycle but fail to model immune cell-mediated pathogenesis. Here we build macrophage-augmented organoids (MaugOs) by integrating macrophages into primary organoids that are cultured from human liver tissues. We test the infections of two RNA viruses, hepatitis E virus and SARS-CoV-2, and one DNA virus, monkeypox virus, which either primarily or secondarily affect the human liver. In all three models of acute viral diseases, MaugOs recapitulate infection and the resulting inflammatory response, although to different levels. We use this system to dissect the multifunctional role of human bile on hepatitis E virus replication and the inflammatory response through distinct mechanisms of action. We also show that MaugOs recapitulate features of inflammatory cell death triggered by hepatitis E virus infection when integrated with pro-inflammatory macrophages. Furthermore, we demonstrate a proof of concept in MaugOs for development of multitarget therapeutics that simultaneously target the virus, inflammatory response and the resultant inflammatory cell death.

Plasmacytoid dendritic cell sensing of hepatitis E virus is shaped by both viral and host factors

Type I and III interferons critically protect the host against viral infection. Previous studies showed that IFN responses are suppressed in cells infected by hepatitis E virus (HEV). Here, we studied the anti-HEV function of IFN secreted by plasmacytoid dendritic cells (pDCs), specialized producers of IFNs. We showed that pDCs co-cultured with HEV-replicating cells secreted IFN in a cell contact-dependent manner. This pDC response required the endosomal nucleic acid sensor TLR7 and adhesion molecules. IFNs secreted by pDCs reduced viral spread. Intriguingly, ORF2, the capsid protein of HEV, can be produced in various forms by the infected cells, and we wanted to study their role in anti-HEV immune response. During infection, a fraction of ORF2 localizes into the nucleus, and glycosylated forms of ORF2 are massively secreted by infected cells. We showed that glycosylated ORF2 potentiates the recognition of infected cells by pDCs, by regulating cell contacts. On the other hand, nuclear ORF2 triggers immune response by IRF3 activation. Together, our results suggest that pDCs may be essential to control HEV replication.

Thermal Inactivation of Hepatitis E Virus: A Narrative Review

Hepatitis E virus (HEV) infection is an emerging infectious disease. HEV-1 and HEV-2 infect humans through contaminated water and foods, mainly in developing countries. HEV-3 and HEV-4 also infect humans through contaminated food and are thought to be zoonotic infections occurring in both developing and developed countries. A vaccine for hepatitis E is licensed in only limited countries. The inactivation of infectious HEV is very important to ensure the safety of drinking water and foods. HEV-3 and HEV-4 RNA have been detected in some pig liver products, and it is possible that these foods may represent an infectious source of HEV. In this article, previous publications on the heat inactivation and heat stability of HEV are collected, and we discuss the present assessment of the heat inactivation of HEV. The thermal stability of HEV infection in cell culture systems and pig bioassays has been demonstrated, while the efficacy of the method of thermal inactivation using plasma products has not yet been established. Here, we propose that the treatment of HEV-contaminated foods at 95 °C for 10 min is one of the safest options for the inactivation of HEV.

Structural basis for hepatitis E virus neutralization by potent human antibodies

Antibodies targeting the hepatitis E virus (HEV) surface capsid protein (CA) are essential for infection control and resolution, yet their molecular and functional attributes remain largely elusive. We characterized 144 human HEV-CA-specific monoclonal antibodies cloned from the memory B cells of HEV-exposed individuals. Most human anti-CA antibodies cross-reacted with all HEV genotype variants, and a subset also recognized the zoonotic rat hepatitis E virus. HEV antibody repertoire was diverse and contained highly potent neutralizing antibodies binding to the CA protruding (P) domain. Structural analyses of CA protein complexed with three potent and broad HEV antibodies uncovered a neutralizing site located on monomeric P domain loops at the apex of the viral spike. These findings provide valuable insights into the protective humoral response to HEV and offer a framework for the rational design of HEV vaccines and immunotherapies.

Research Progress on Hepatitis E Virus Culture

Hepatitis E virus (HEV) is a zoonotic pathogen and the main cause of acute viral hepatitis in China, resulting in a significant burden on public health. Developing a highly efficient in vitro culture system for HEV is crucial for understanding the determinants of HEV infection in humans and other animals, the pathogenic mechanisms, as well as the screening and evaluation of antiviral drugs. In this paper, the research progress on HEV in vitro culture systems is reviewed to provide a convenient reference for further research on HEV, aiding comprehensive efforts toward the widespread prevention and control of related diseases.

Plasmid-Based Reverse Genetics System Enabling One-Step Generation of Genotype 3 Hepatitis E Virus

Hepatitis E virus (HEV) is a positive-sense, single-stranded RNA virus that poses a significant public health risk, yet its study is hindered by the complexity of conventional RNA-based reverse genetics systems. These systems require multiple steps, including genome cloning, in vitro transcription, and capping, making them labor-intensive and susceptible to RNA degradation. In this study, we developed a single-step, plasmid-based HEV expression system that enabled direct intracellular transcription of the full-length HEV genome under a cytomegalovirus immediate-early (CMV-IE) promoter. The viral genome was flanked by hammerhead (HH) and hepatitis delta virus (HDV) ribozymes to ensure precise self-cleavage and the generation of authentic 5' and 3' termini. This system successfully supported HEV genome replication, viral protein expression, and progeny virion production at levels comparable to those obtained using in vitro-transcribed, capped HEV RNA. Additionally, a genetic marker introduced into the plasmid construct was stably retained in progeny virions, demonstrating the feasibility of targeted genetic modifications. However, plasmid-derived HEV exhibited delayed replication kinetics, likely due to the absence of an immediate 5' cap. Attempts to enhance capping efficiency through co-expression of the vaccinia virus capping enzyme failed to improve HEV replication, suggesting that alternative strategies, such as optimizing the promoter design for capping, may be required. This plasmid-based HEV reverse genetics system simplifies the study of HEV replication and pathogenesis and provides a versatile platform for the genetic engineering of the HEV genome.

Can Adoptive Immunotherapy With Hepatitis E Virus (HEV)-Specific T Cells Address the Unmet Need in Refractory Chronic HEV Infection?

Chronic hepatitis E virus (HEV) infection, which primarily affects the immunocompromised, can rapidly progress to liver fibrosis and cirrhosis if untreated. However, current therapeutic options are extremely limited and have significant adverse effects. Over the past decade, virus-specific T-cell therapy has shown promise as an alternative safe and effective treatment strategy for other refractory viral infections such as cytomegalovirus, adenovirus, and polyomavirus infections in hematopoietic stem cell and solid organ transplant recipients. Given the key role of T lymphocytes in the control of HEV replication and the fact that HEV-specific T-cell responses are typically diminished in immunosuppressed patients with persistent HEV infection, adoptive immunotherapy with HEV-specific T cells could serve as a novel addition to the HEV treatment repertoire, which is in dire need of expansion.

The Prevalence, Risk Factors, and Outcomes of Hepatitis E Virus Infection in Solid Organ Transplant Recipients in a Highly Endemic Area of Italy

Hepatitis E virus (HEV) infection can become chronic in immunocompromised patients, like solid organ transplant recipients (SOTRs). We evaluated HEV prevalence, risk factors, and outcomes among SOTRs in a hyperendemic HEV area. Three hundred SOTRs were enrolled from April to July 2019 and tested for anti-HEV IgM and IgG and HEV RNA. Sixty-three recipients (21%) were positive for any HEV marker. HEV infection was independently associated with older age and pork liver sausage consumption. Three viremic recipients harbored genotype 3e and 3f according to HEV RNA sequencing and phylogenetic analysis. Overall, 10 recipients had markers of active/recent infection (HEV RNA and/or anti-HEV IgM) and were followed up prospectively. Five of them spontaneously resolved their HEV infection. In two recipients, HEV clearance was achieved only through immunosuppression reduction, while three needed ribavirin therapy to achieve virologic resolution. We observed a chronic course in 30% of SOTRs with active/recent HEV infection. No association was found between tacrolimus assumption and chronicization. In conclusion, we found a high prevalence of infection among SOTRs attending a transplant center in a hyperendemic Italian HEV region. Systematic screening for all HEV markers and dietary education for infection control are needed for transplant recipients.

Weighted prevalence and associated risk factors of hepatitis E virus antibodies among pregnant women in rural Burkina Faso using dried blood spot samples

AIM

To estimate the weighted prevalence of hepatitis E virus (HEV) antibodies and risk factors among pregnant women in Burkina Faso and to evaluate the efficiency of dried blood spots (DBS) in detecting HEV antibodies.

METHODS

We first evaluated the efficiency of DBS detecting HEV antibodies by comparing 62 DBS with matched serum samples using recomWell IgG and IgM kits (Mikrogen Diagnostik). Anti-HEV immunoglobulin G (IgG) and immunoglobulin M (IgM) were identified in 491 DBS samples collected from pregnant women in Burkina Faso using recomWell kits. HEV RNA was tested using HEV nested polymerase chain reaction among HEV-antibodies positive. The survey-weighted method was applied for prevalence calculations and risk factors analysis.

RESULTS

The detection of anti-HEV IgG and anti-HEV IgM in DBS samples revealed a sensitivity of 96.7% and 76.7% and a specificity of 100% and 93.8% compared to serum samples, respectively. Among 491 pregnant women tested, the weighted prevalence of anti-HEV IgG was 18.6%, and anti-HEV IgM was 2.5%, with no HEV RNA detected. A significant age-related increase was observed in the prevalence of anti-HEV IgG (p < 0.001), while no significant was found for anti-HEV IgM-positivity (p = 0.1451). Multiparity was significantly associated with anti-HEV IgG-positivity, while women aged 25-34 years were at higher risk of anti-HEV IgM-positivity.

CONCLUSION

This study revealed that DBS is a reliable alternative for HEV seroepidemiological studies, especially in resource-limited settings, although further investigation is needed for anti-HEV IgM detection. The weighted prevalence of anti-HEV IgG was 18.6% and anti-HEV IgM was 2.5%, highlighting the ongoing burden of HEV infection, particularly in high-risk groups like pregnant women in rural Burkina Faso.

Hepatitis E Infection in Immunocompromised Patients Previously Treated With Rituximab

Hepatitis E virus (HEV) infection is a frequent cause of acute viral hepatitis. Immunocompromised patients, especially those under anti-CD20 regimens, are prone to chronic or treatment-resistant courses of hepatitis E. We report a case of chronic HEV infection in a 36-year-old man with a history of thrombotic thrombocytopenic purpura treated with rituximab 6 months ago, who presented with new-onset painless jaundice and malaise. Laboratory tests and imaging revealed signs of inflammation and hepatic dysfunction. Due to initial suspicion of autoimmune hepatitis, corticosteroid therapy was started. However, liver biopsy and positive HEV RNA value redefined the diagnosis. Serology tests revealed initially acute infection, which later progressed to chronic hepatitis E infection. Treatment with ribavirin, along with supportive care, achieved significant clinical and laboratory improvement, resolving jaundice, restoring normal transaminase and suppressing HEV RNA values. Further review of the literature highlights the impact of immunosuppression caused by anti-CD20 therapies on HEV infection, as well as the challenges in both treatment and achieving sustained virus clearance in such patients. Moreover, this report underlines the importance of HEV screening in patients with hepatitis who have undergone anti-CD20 therapies, shedding light on a situation that is not well described in the literature and should not be overlooked, even in developed countries.

Mechanisms and aetiology-dependent treatment of acute liver failure

This review compiles the mechanisms of acute liver failure (ALF) as well as the current and potential therapeutic approaches, including aetiology-specific treatment, and the issues encountered with such approaches. On a cellular level, ALF is characterized by massive hepatocyte death due to different types of cellular demise. Compensatory hyperplasia and functional recovery are possible when the regenerative capacity is sufficient to sustain hepatic function. ALF has a high mortality of about 30% and can lead to death in a very short time despite maximum therapeutic intervention. Besides aetiology-specific therapy and intensive care, the therapeutic option of emergency liver transplantation has significantly improved the prognosis of patients with ALF. However, due to limiting factors such as organ shortage, many patients die on the waiting list. In addition to graft assessment, machine perfusion may have the potential to recondition marginal organs and thus expand the organ donor pool.

Genetic Diversity and Molecular Evolution of Hepatitis E Virus Within the Genus Chirohepevirus in Bats

Hepatitis E virus (HEV) is a major zoonotic pathogen causing hepatitis E, with strains identified in various animal species, including pigs, wild boar, rabbits, deer, camels, and rats. These variants are capable of crossing species barriers and infecting humans. HEV belongs to the family Hepeviridae, which has recently divided into two subfamilies: Orthohepevirinae and Parahepevirinae, and five genera: Paslahepevirus, Avihepevirus, Rocahepevirus, Chirohepevirus, and Piscihepevirus. Recent advances in high-throughput sequencing, particularly of bat viromes, have revealed numerous HEV-related viruses, raising concerns about their zoonotic potential. Bat-derived HEVs have been classified into the genus Chirohepevirus, which includes three distinct species. In this study, we analyzed 64 chirohepevirus sequences from 22 bat species across six bat families collected from nine countries. Twelve sequences represent complete or nearly complete viral genomes (>6410 nucleotides) containing the characteristic three HEV open reading frames (ORFs). These strains exhibited high sequence divergence (>25%) within their respective host genera or species. Phylogenetic analyses with maximum likelihood methods identified at least seven distinct subclades within Chirohepevirus, each potentially representing an independent species. Additionally, the close phylogenetic relationship between chirohepevirus strains and their bat hosts indicates a pattern of virus-host co-speciation. Our findings expand the known diversity within the family Hepeviridae and provide new insights into the evolution of bat-associated HEV. Continued surveillance of chirohepevirus will be essential for understanding its potential for zoonotic transmission and public health risks.

Safety and immunogenicity of hepatitis E vaccine in compensated liver cirrhosis with chronic hepatitis B

OBJECTIVES

Hepatitis E virus (HEV) is a global health concern that causes acute hepatitis with severe consequences, particularly in patients with chronic liver disease. Despite the availability of a recombinant hepatitis E vaccine (Hecolin), its safety and immunogenicity in patients with pre-existing liver cirrhosis remain uncertain. This study aimed to assess the safety and immunogenicity of Hecolin in individuals with compensated liver cirrhosis who have chronic hepatitis B (CHB).

METHODS

This study was conducted in Shenzhen City, China, from November 2019 to June 2022. The adult participants were stratified into untreated CHB, CHB treatment, CHB cirrhosis, and control groups based on their disease status. Safety assessment included adverse events and liver function tests. Serological samples were collected before vaccination and 1 month after both the first and third doses of vaccination to assess anti-HEV IgG antibodies.

RESULTS

A total of 162 eligible participants, including 43 with CHB cirrhosis, 50 with treated CHB, 50 with untreated CHB, and 19 controls were included in the study. A total of 157 (96.9%) participants received three doses of the vaccine. Safety analysis revealed 7-day local adverse events in 13.95.0%, 24.0%, 12.0%, and 5.26% and systemic adverse events in 6.98%, 12.0%, 4.0%, and 0% across the cirrhosis, treated, untreated, and control groups, respectively. No serious adverse events were deemed to be causally related to vaccination. In the per-protocol set for immunogenicity, all vaccinated participants with cirrhosis (95% CI, 88.1-100%) were seroconverted, and 82.8% (24/29) had anti-HEV IgG levels higher than 1.0 WU/mL at 1 month after the final dose (median, 38 days; interquartile range, 31-44).

DISCUSSION

This study suggests that Hecolin is safe and immunogenic in patients with CHB with compensated liver cirrhosis, supporting its use in preventing HEV superinfection in this high-risk population.

Heterogeneity in the seroprevalence of hepatitis E virus among hospital attendees: a retrospective study in Shanghai, China

BACKGROUND

Hepatitis E virus (HEV) infection is endemic in China. However, there are scarce data of HEV infection among hospital attendees seeking medical treatment or examination for various reasons.

OBJECTIVE

We aim to investigate the prevalence and incidence of HEV infection by time, age, sex, and across departments in a tertiary hospital.

METHODS

Paired results of anti-HEV immunoglobulin G (IgG) and IgM of 31,181 unique subjects during 2021-2022 were analysed.

RESULTS

Overall seropositivity (95% confidence interval) of anti-HEV IgG and IgM was 41.25% (40.71%-41.80%) and 2.35% (2.19%-2.53%), respectively. Acute hepatitis E was more prevalent during winter-early spring and among adults aged 31-70. Anti-HEV IgG seroprevalence increased with age, levelling off at > 60 years of age. Not only the seropositivity, but also the levels of anti-HEV IgG were significantly lower in women than men of middle and old age. Young patients from the Department of Neurology had a significantly higher ratio of past HEV infection, while patients with manifestations of hepatitis, gastrointestinal symptoms or hematological diseases had higher seropositivity of anti-HEVIgM and should have high priority to HEV screening.

CONCLUSION

Heterogeneity of HEV seroprevalence was noted at different times of the year, between sexes, among age groups and across departments in general hospital. The concentration of HEV-infected patients in a few departments supports a more focused screening strategy in health-care settings.

Effectiveness of a hepatitis E vaccine against medically-attended symptomatic infection in HBsAg-positive adults from a test-negative design study

The effectiveness of the hepatitis E vaccine in high-risk groups, such as chronic hepatitis B (CHB) patients, remains understudied. A key clinical manifestation of CHB is the persistent positivity of hepatitis B surface antigen (HBsAg). We conducted a test-negative design study involving 2,926 HBsAg-positive individuals (born 1941-1991; median age 49.0; male-to-female ratio of 1.4), identified through a hepatitis surveillance system, as part of the phase 3 trial (NCT01014845) of the recombinant hepatitis E vaccine HEV 239 (Hecolin). This system monitored suspected hepatitis cases and performed diagnoses across 11 townships in Dongtai, Jiangsu, China, from 2007 to 2017. Vaccine effectiveness of HEV 239 was assessed by comparing vaccination status between confirmed 96 hepatitis E cases and 2830 test-negative controls, using logistic regression adjusted for sex and age. We found that HEV 239 vaccination was associated with a reduced risk of hepatitis E among HBsAg-positive individuals, with an estimated effectiveness of 72.1% [95% confidence interval (CI) 11.2-91.2], and 81.5% (95% CI 35.9-94.6) among phase 3 trial participants. Our findings show that HEV 239 is highly effective in HBsAg-positive adults, supporting its future recommended use in this population.

Descriptive Comparative Transcriptomic Analysis of Genotype IV SHEV ORF3-Expressing HepG2 Cells

Background: Swine hepatitis E (HEV) is a zoonotic infectious disease caused by the swine hepatitis E virus (SHEV). Open reading frame 3 (ORF3) is a key virulence factor in swine HEV, playing a crucial role in the release of viral particles, the modulation of the host innate immune response, and regulation of autophagy and apoptosis, etc. However, its main function and pathogenic mechanism remain incompletely understood. Results: In our study, adenoviruses ADV4-ORF3 and ADV4-GFP were successfully constructed and mediated the overexpression of enhanced green fluorescent protein (EGFP)-ORF3 and EGFP in HepG2 cells. A total of 217 differentially expressed messenger RNAs (mRNAs) were screened by high-throughput sequencing, and 27 statistically significant differentially expressed genes were screened for further quantitative real-time reverse transcription (qRT-PCR) verification by functional enrichment (Gene Ontology [GO] and Kyoto Encyclopedia of Genes and Genomes [KEGG]). They are mainly involved in six pathways: the cellular response to unfolded protein, inflammatory response, cytokine activity, TNF signaling pathway, influenza A, and pathways in cancer. In a comparative analysis of transcriptome and mRNA expression profiles of lncRNA sequencing, the results showed that 3 mRNAs of GPX1, MDM4, and CLDN and 39 transcripts overlapped and have been identified. Conclusions: Eight differential genes, HSPA1A, HSPA1B, PLD3, RELA, GPI, SAMHD1, RPS6KA4, and PIK3CB, were successfully verified. Comparing and analyzing the results of the two sequencing methods indicated that the 3 mRNAs of GPX1, MDM4, and CLDN and 39 transcripts overlapped and have been identified in SHEV ORF3-expressing HepG2 cells, which has laid a genetic foundation for the physiological function and mechanism of SHEV ORF3.

Establishment of enterically transmitted hepatitis virus animal models using lipid nanoparticle-based full-length viral genome RNA delivery system

BACKGROUND

Enterically transmitted hepatitis viruses, such as hepatitis A virus (HAV) and hepatitis E virus (HEV), remain notable threats to public health. However, stable and reliable animal models of HAV and HEV infection are lacking.

OBJECTIVE

This study aimed to establish HAV and HEV infections in multiple small animals by intravenously injecting lipid nanoparticle (LNP)-encapsulated full-length viral RNAs (LNP-vRNA).

DESIGN

In vitro transcribed and capped full-length HAV RNA was encapsulated into LNP and was intravenously inoculated to Ifnar-/- mice, and HEV RNA to rabbits and gerbils. Virological parameters were determined by RT-qPCR, ELISA and immunohistochemistry. Liver histopathological changes were analysed by H&E staining. Antiviral drug and vaccine efficacy were further evaluated by using the LNP-vRNA-based animal model.

RESULTS

On intravenous injection of LNP-vRNA, stable viral shedding was detected in the faeces and infectious HAV or HEV was recovered from the livers of the inoculated animals. Liver damage was observed in LNP-vRNA (HAV)-injected mice and LNP-vRNA (HEV)-injected rabbits. Mongolian gerbils were also susceptible to LNP-vRNA (HEV) injections. Finally, the antiviral countermeasures and in vivo function of HEV genome deletions were validated in the LNP-vRNA-based animal model.

CONCLUSION

This stable and standardised LNP-vRNA-based animal model provides a powerful platform to investigate the pathogenesis and evaluate countermeasures for enterically transmitted hepatitis viruses and can be further expanded to other viruses that are not easily cultured in vitro or in vivo.

Liver diseases: epidemiology, causes, trends and predictions

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

Deciphering the hepatitis E virus ORF1: Functional domains, protein processing, and patient-derived mutations

Hepatitis E virus (HEV) is a major cause of acute and chronic hepatitis in humans. The HEV open reading frames (ORF1) encodes a large non-structural protein essential for viral replication, which contains several functional domains, including helicase and RNA-dependent RNA polymerase. A confusing aspect is that, while RNA viruses typically encode large polyproteins that rely on their enzymatic activity for processing into functional units, the processing of the ORF1 protein and the mechanisms involved remain unclear. The ORF1 plays a pivotal role in the viral life cycle, thus mutations in this region, especially those occurring under environmental pressures such as during antiviral drug treatment, could significantly affect viral replication and survival. Here, we summarize the recent advances in the functional domains, processing, and mutations of ORF1. Gaining a deeper understanding of HEV biology, particularly focusing on ORF1, could facilitate the development of new strategies to control HEV infections.

Hepatitis E virus infection in immunosuppressed patients and its clinical manifestations

BACKGROUND & AIMS

Hepatitis E virus (HEV) is a main cause of acute hepatitis globally. However, immunosuppressed patients regularly develop chronic courses. The aim of this study was to analyse the current status of HEV diagnostics, characterize clinical manifestations and identify risk factors for complicated HEV infections.

METHODS

In this retrospective study at two large hospitals, 512 patients with borderline and positive anti-HEV-IgM and 94 patients with positive HEV-PCR between January 1999 and May 2023 were included.

RESULTS

Detection by anti-HEV-IgM-ELISA led to a positive HEV-PCR in only 17.9 %. Amongst patients with positive HEV-PCR, 61 had underlying immunosuppression and 23 were patients after solid organ transplantation (SOT). All 13 patients with chronic HEV infections were immunosuppressed. Generally, immunosuppression led to higher HEV-RNA concentrations and a higher probability of receiving immediate treatment. However, all fulminant courses with liver failure happened in patients without immunosuppression. Immunocompetent patients showed symptoms more frequently and primarily had higher bilirubin levels indicating more severe liver damage. A risk factor for delayed or failed viral clearance after SOT was the administration of mTOR inhibitors.

CONCLUSIONS

Fulminant HEV infections happen primarily in immunocompetent patients. Nevertheless, immunosuppressed patients bear the risk of undetected, prolonged HEV infections, reflected by the rare occurrence of symptoms.

Global vaccination against hepatitis E virus: position paper from the European Society of Clinical Microbiology and Infectious Diseases Viral Hepatitis Study Group

SCOPE

Hepatitis E virus (HEV) is a significant global health issue, impacting both low- and middle-income countries and industrialized nations. HEV genotypes 1 and 2, primarily transmitted through contaminated water, are endemic in low- and middle-income countries, whereas genotypes 3 and 4 are zoonotically transmitted in industrialized regions. Acute HEV infection poses severe risks, particularly to pregnant women and immunocompromised individuals, whereas chronic HEV infection leads to serious complications in those with pre-existing liver disease and transplant recipients. The development of an HEV vaccine offers new prevention opportunities, though its availability and integration into global immunization programmes remain limited.

METHODS

This position paper was developed by the European Society of Clinical Microbiology and Infectious Diseases Viral Hepatitis Study Group through an extensive review of clinical data, safety profiles, efficacy, and immunogenicity of HEV vaccines. The study group focused particularly on high-risk and special populations, synthesizing global health insights and incorporating recommendations from the Strategic Advisory Group of Experts to formulate strategies for wider HEV vaccination use.

QUESTIONS ADDRESSED IN THE POSITION PAPER

The position paper evaluates the efficacy and safety of HEV vaccines in both general and special populations. It identifies key barriers to the integration of HEV vaccines into routine immunization programmes, including infrastructure limitations, costs, and vaccine accessibility. The paper also proposes strategies to overcome these challenges and improve vaccine distribution. Furthermore, it addresses ways to enhance public awareness and international cooperation to promote HEV vaccination efforts globally.

IMPLICATIONS

European Society of Clinical Microbiology and Infectious Diseases Viral Hepatitis Study Group recommends HEV vaccination for high-risk groups, including women of childbearing age, patients with chronic liver diseases, and immunosuppressed individuals. Prioritizing investments in vaccine logistics, integrating diagnostics, and educational outreach can enhance uptake.

Utility of hypervariable region in hepatitis E virus for genetic evolution analysis and epidemiological studies

Clinical and experimental studies have advanced our understanding of hepatitis E virus (HEV) infection; however, translating the findings to improve prevention and clinical outcomes remains challenging. Phylogenetic analyses of HEV show inconsistencies due to variations in the nucleotide regions studied. This study examined specific HEV regions to facilitate comprehensive molecular and phylogenetic analyses by examining the complete genome and commonly studied partial genome regions. We compared topological similarities between phylogenetic trees and evaluated evolutionary divergence using base substitutions and pairwise distances. The hypervariable region (HVR) showed the closest topology (Robinson-Foulds, Jaccard Robinson-Foulds and clustering information) to the complete genome and a higher mutation rate, resulting in longer branch lengths and clearer genotypic distinctions. Pairwise analysis revealed greater intra- and intergenotypic diversity in the HVR than in other regions. The higher base substitution rate and longer branch lengths of HVR suggest its key role in genotype evolution. Classifying HEV using HVR instead of the other partial genomic regions can reveal subtypes that more accurately reflect the genetic characteristics of HEV. Future research could focus on HVRs to better compare clinical symptoms and genetic features of HEV.

Incidence and risk factors of hepatitis E virus infection in women with gynecological tumors in Eastern China

Background

Recently, there has been increasing interest in the exploration of the association between the hepatitis E virus (HEV) infection and malignancies; however, epidemiological data for HEV infection among women with a gynecological tumors (GT) are limited. Herein, we investigated the correlation between HEV and GT in Chinese women.

Methods

We recruited 452 women diagnosed with a primary GT and 452 healthy volunteers to investigate the possible routes and risk factors for HEV infection. The serum antibody levels of anti-HEV IgG and IgM were measured by enzyme-linked immunoassays once a year.

Results

After a median follow-up time of 5.4 years (range 4 to 7 years), the overall detection rate of anti-HEV antibodies in patients with GT and in controls were 69/452 (15.27%) and 23/452 (5.09%) (P = 0.001), respectively. The seroprevalence of anti-HEV IgG antibodies was significant higher in patients with GT (15.27%) than in healthy controls (5.09%) (P = 0.001). Moreover, 13 (2.88%) patients with GT were positive for IgM antibodies, while only 4 (0.88%) healthy controls tested positive for anti-HEV IgM antibodies (P = 0.028). The highest prevalence of HEV antibodies were detected in patients with ovarian borderline tumors (40%), followed by patients with ovarian cancer (20.54%) and endometrial cancer (18.46%). Multivariable analysis revealed that contact with dogs (OR, 1.88; 95% CI [1.10-3.22]; P = 0.015) and a history of anti-tumor chemotherapy (OR, 1.85; 95% CI [1.07-3.20]; P = 0.028) were independent risk factors for HEV infection.

Conclusion

Overall, the present study showed that patients with GT are more susceptible to HEV infection in Eastern China, particularly in patients with ovarian borderline tumors. Thus, effective strategies are needed to reduce HEV infection in patients with GT.

One-Pot Assay Based on CRISPR/Cas13a Technology for HEV RNA Point-of-Care Testing

Hepatitis E virus (HEV) poses a serious threat to both public health and animal food safety, thereby highlighting the demands for rapid, sensitive, and easy-to-use detection. This study aimed to develop a One-Pot assay using CRISPR/Cas13a for detecting HEV RNA, suitable for point-of-care testing (POCT) in resource-limited settings. CRISPR/Cas13a combined with reverse transcription polymerase chain reaction (RT-PCR) and reverse transcription recombinase-aided amplification (RT-RAA) was applied to a One-Pot assay device. Additionally, a large cohort of HEV-infected patient (154) and animal (104) specimens was utilized for validation. The RT-PCR/RT-RAA + CRISPR/Cas13a assays for HEV RNA detection (genotypes: HEV-1, HEV-3, and HEV-4) were established, optimized, and validated, achieving a limit of detection (LoD) of 1 copy/μL and 100% specificity. In the application validation for HEV infection, the positive rates of the RT-PCR + CRISPR and RT-RAA + CRISPR assays were 98.6% and 89.6% for patients, and 96.6% and 88.8% for animals, respectively, which were superior to those of RT-qPCR. Furthermore, sample rapid lysis, reagent lyophilization, and the One-Pot device were integrated to construct a One-Pot assay with an LoD of 102 copies/μL. Despite slight decreases in sensitivity, the One-Pot assay significantly reduces the assay time to 35 min, making it easy to perform, minimizing contamination, and meeting the requirements for screening. We developed a One-Pot assay of HEV RNA using the CRISPR/Cas13a which effectively realizes a POCT test and maximizes the impetus for POCT implementation and shows potential as a valuable tool for detecting and monitoring HEV infection.

Hepatitis E virus infects human testicular tissue and Sertoli cells

Globally, hepatitis E virus (HEV) infections are prevalent. The finding of high viral loads and persistent viral shedding in ejaculate suggests that HEV replicates within the human male genital tract, but its target organ is unknown and appropriate models are lacking. We aimed to determine the HEV tropism in the human testis and its potential influence on male reproductive health. We conducted an ex vivo culture of human testis explants and in vitro culture of primary human Sertoli cells. Clinically derived HEV genotype 1 (HEV1) and HEV3 virions, as well as rat-derived HEV-C1, were used for inoculation. Transcriptomic analysis was performed on testis tissues collected from tacrolimus-treated rabbits with chronic HEV3 infection. Our findings reveal that HEV3, but not HEV1 or HEV-C1, can replicate in human testis explants and primary human Sertoli cells. Tacrolimus treatment significantly enhanced the replication efficiency of HEV3 in testis explants and enabled successful HEV1 infection in Sertoli cells. HEV3 infection disrupted the secretion of several soluble factors and altered the cytokine microenvironment within primary human Sertoli cells. Finally, intratesticular transcriptomic analysis of immunocompromised rabbits with chronic HEV infection indicated downregulation of genes associated with spermatogenesis. HEV can infect the human testicular tissues and Sertoli cells, with increased replication efficiency when exposed to tacrolimus treatment. These findings shed light on how HEV may persist in the ejaculate of patients with chronic hepatitis E and provide valuable ex vivo tools for studying countermeasures.

HEV Infection in Beta-Thalassemia Patients

Thalassemia is an inherited hematological disorder characterized by a decrease in the synthesis of or absence of one or more globin chains. Hepatitis E virus (HEV) is a major cause of acute viral hepatitis, constituting a major global health burden and emerging as a critical public health concern. HEV infection is mainly transmitted via the fecal-oral route; however, parenteral transmission through blood components has been reported in both developing and developed countries. Although HEV infection is typically self-limiting, immunocompromised individuals, patients with chronic liver disease, and thalassemic patients are at a heightened risk of contracting the infection and may develop chronic hepatitis and life-threatening complications that require treatment. The reported prevalence rates of HEV in thalassemia patients vary significantly by country. Age, gender, residential area, and the cumulative amount of blood transfusions received have been identified as associated risk factors for HEV infection. In order to enhance blood safety and ensure the protection of vulnerable patient populations, such as thalassemia patients, several countries have introduced universal or targeted HEV screening policies in blood donations. Other preventive measures include vigilant monitoring of thalassemic patients and screening for anti-HEV antibodies. The aim of this review is to explore the prevalence, risk factors, clinical impact and management of HEV infection in patients with thalassemia.

Case of Fatal Hepatitis Related to HEV-3 Infection in Central Italy

Hepatitis E virus (HEV) is a global health problem, causing an estimated 20 million infections annually. Thus, the management of HEV requires special consideration. In developed countries, hepatitis E is mainly recognized as a foodborne disease (mainly transmitted via undercooked meat consumption) that is generally caused by genotype 3 and 4 circulating in various animals, including pigs and wild boars. The current absence of officially recognized protocols for the analysis of HEV in foods and the lack of awareness of this disease among healthcare workers, together with the high percentage of asymptomatic cases, make HEV infection highly underestimated. Most HEV-3 infections in immunocompetent individuals are self-limited. Nevertheless, the possibility of serious forms of liver disease, especially in patients with co-morbidities, should be considered because it can lead to a fatal outcome. Here, we report a case of fatal hepatitis related to HEV-3 infection in a 67-year-old male patient with underlying chronic liver disease (CLD) and living in a region where a high prevalence and genetic heterogeneity of HEV-3 in wild boar has been recently demonstrated. Our case report describes the interdisciplinary approach used (from the diagnosis to the virus phylogenetic characterization) in order to improve epidemiologic HEV surveillance in central Italy.

Association of IL1RN VNTR and NKG2A polymorphisms with hepatitis E infection, a case study from western India

Interleukin 1 receptor antagonist (IL1RN) is a competitive inhibitor of interleukin 1 (IL-1). Natural killer cells (NK cells) contribute to the elimination of viruses by their antiviral effector function, which depends on a balance between inhibitory and activating receptor genes such as NKG2D and NKG2A. Using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assays, the association of intronic single-nucleotide polymorphisms (SNPs) in these genes with viral infection were assessed in 111 patients with hepatitis E virus (HEV) infection and 222 HEV-naive healthy controls. An SNP in the IL1RN (VNTR) gene revealed allele 2 to be associated with protection against HEV infection (IL1RN *1/*1 vs. IL1RN *2/*2, OR = 0.26, 95% CI = 0.14-0.47, p < 0.001). Similarly, a polymorphism in the intronic region of NKG2A revealed an association with protection in a co-dominant model (A/A vs. A/G: OR = 0.40; 95% CI = 0.24-0.67; A/A vs. G/G: OR = 0.25; 95% CI = 0.10-0.57; p < 0.05) and an association with susceptibility in a dominant model (A/A + A/G vs. G/G: OR = 2.28; 95% CI = 1.06-4.93; p < 0.05) and a recessive model (AA vs. AG + GG: OR = 2.71; 95% CI = 1.66-4.48; p < 0.001). Our data suggest that genetic polymorphisms in host NKG2A and IL1RN have both protective and detrimental roles in HEV infection, although their impact on disease outcome remains unknown.

Acacetin, a Natural Flavone with Potential in Improving Liver Disease Based on Its Anti-Inflammation, Anti-Cancer, Anti-Infection and Other Effects

Liver disease is a global public problem, and the cost of its therapy is a large financial burden to governments. It is well known that drug therapy plays a critical role in the treatment of liver disease. However, present drugs are far from meeting clinical needs. Lots of efforts have been made to find novel agents to treat liver disease in the past several decades. Acacetin is a dihydroxy and monomethoxy flavone, named 5,7-dihydroxy-4'-methoxyflavone, which can be found in diverse plants. It has been reported that acacetin exhibits multiple pharmacological activities, including anti-cancer, anti-inflammation, anti-virus, anti-obesity, and anti-oxidation. These studies indicate the therapeutic potential of acacetin in liver disease. This review discussed the comprehensive information on the pathogenesis of liver disease (cirrhosis, viral hepatitis, drug-induced liver injury, and hepatocellular carcinoma), then introduced the biological source, structural features, and pharmacological properties of acacetin, and the possible application in preventing liver disease along with the pharmacokinetic and toxicity of acacetin, and future research directions. We systemically summarized the latest research progress on the potential therapeutic effect of acacetin on liver disease and existing problems. Based on the present published information, the natural flavone acacetin is an anticipated candidate agent for the treatment of liver disease.

Ritonavir's Evolving Role: A Journey from Antiretroviral Therapy to Broader Medical Applications

Ritonavir is a protease inhibitor initially developed for HIV treatment that is now used as a pharmacokinetic booster for other antiretrovirals due to it being a cytochrome P450 3A4 enzyme and P-glycoprotein inhibitor. Consequently, ritonavir is of special interest for repurposing in other diseases. It had an important role in battling the COVID-19 pandemic as a part of the developed drug Paxlovid® in association with nirmatrelvir and has shown effects in hepatitis and other pathogenic diseases. Ritonavir has also shown promising results in overcoming drug resistance and enhancing the efficacy of existing chemotherapeutic agents in oncology. Evidence of cancer repurposing potential was demonstrated in cancers such as ovarian, prostate, lung, myeloma, breast, and bladder cancer, with several mechanisms of action presented. In vitro studies indicate that ritonavir alone can inhibit key pathways involved in cancer cell survival and proliferation, causing apoptosis, cell cycle arrest, endoplasmic reticulum stress, and metabolic stress due to the inhibition of molecules like heat shock protein 90 and cyclin-dependent kinases. Ritonavir also causes resistant cells to become sensitized to anticancer drugs like gemcitabine or docetaxel. These findings indicate that repurposing ritonavir, either on its own or in combination with other medications, could be a promising approach for treating various diseases. This is particularly relevant in cancer therapy, where ritonavir repurposing is the central focus of this review.

Recent decline in hepatitis E virus prevalence among wild boars in Japan: Probably due to countermeasures implemented in response to outbreaks of classical swine fever virus infection

Previous studies have emphasized the necessity of surveillance and control measures for hepatitis E virus (HEV) infection in wild boars, an important reservoir of HEV. To assess the current situation of HEV infection in wild boars in Japan, this study investigated the prevalence and genetic diversity of HEV among wild boars captured in 16 prefectures of Japan during 2018-2023. Serum samples from 968 wild boars were examined for anti-HEV IgG antibodies and HEV RNA. The prevalence of anti-HEV IgG varied geographically from 0 % to 35.0 %. HEV RNA was detected in 3.6 % of boars, with prevalence varying by prefecture from 0 % to 22.2 %. Genotype 3 was the most prevalent genotype (91.9 %), followed by genotype 4 (5.4 %), with one strain closely related to genotype 6. The prevalence of HEV infection among wild boars decreased from 2018/2019 to 2022/2023 with significant declines in levels of anti-HEV IgG antibodies (14.5 % vs. 6.2 %, P < 0.0001) and HEV RNA (7.6 % vs. 1.5 %, P < 0.0001). Regional analysis showed varying trends, with no HEV RNA-positive boars found in several regions in recent years. A plausible factor contributing to the decline in HEV infection is the application of countermeasures, including installing fences to prevent intrusion into pig farms, implemented in response to the emergence of classical swine fever virus (CSFV) infection in wild boars and domestic pigs, with incidents reported annually since 2018. Further investigation is warranted to explore the association between countermeasures to CSFV infection and the decrease in HEV infection among wild boars.

Cost-Effectiveness of Hepatitis E Vaccination Strategies among Patients with Chronic Liver Diseases in China: A Model-Based Evaluation

Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis worldwide, primarily transmitted through contaminated water and food. In patients with chronic liver disease (CLD), HEV infection might worsen the prognosis. This study aimed to evaluate the cost-effectiveness of hepatitis E vaccination strategies in CLD patients. A decision tree-Markov cohort model was used to assess the cost-effectiveness of universal-vaccination, vaccination-following-screening, and no-vaccination strategies in 100,000 CLD patients over their lifetimes, simulating cohorts aged ≥16 years, ≥40 years, and ≥60 years, based on the licensed vaccination ages and typical ages of CLD onset, from a societal perspective. Model parameters were retrieved and estimated from previous publications and government data. The outcomes included HEV-related cases, costs, and the incremental cost-effectiveness ratio (ICER). Compared to no-vaccination, universal-vaccination reduced HEV-related cases by 32.8% to 39.6%, while vaccination-following-screening reduced them by 38.1% to 49.3%. Furthermore, universal-vaccination showed ICERs of USD 6898.33, USD 6638.91, and USD 6582.69 per quality-adjusted life year (QALY) for cohorts aged ≥16, ≥40, and ≥60 years, respectively. Moreover, the vaccination-following-screening strategy significantly enhanced cost-effectiveness, with ICERs decreasing to USD 6201.55, USD 5199.46, and USD 4919.87 per QALY for the cohorts. Additionally, one-way sensitivity analysis identified the discount rate and utility for CLD patients as the key factors influencing ICER. Probabilistic sensitivity analysis indicated the vaccination-following-screening strategy was cost-effective with probabilities of 92.50%, 95.70%, and 95.90% for each cohort. Hepatitis E vaccination in CLD patients costs less than GDP per capita for each QALY gained in China. The vaccination-following-screening strategy may be the optimal option, especially in those over 60 years.

Hepatitis E virus immunosuppressed animal models

Hepatitis E virus (HEV) is an important emerging pathogen producing significant morbidity in immunosuppressed patients. HEV has been detrimental to solid organ transplant (SOT) patients, cancer patients, and HIV-positive patients, where chronic HEV infections occur. Blood-borne transfusions and multiple cases of chronic HEV infection in transplant patients have been reported in the past few decades, necessitating research on HEV pathogenesis using immunosuppressed animal models. Numerous animal species with unique naturally occurring HEV strains have been found, several of which have the potential to spread to humans and to serve as pathogenesis models. Host immunosuppression leads to viral persistence and chronic HEV infection allows for genetic adaptation to the human host creating new strains with worse disease outcomes. Procedures necessary for SOT often entail blood transfusions placing immunosuppressive patients into a "high risk group" for HEV infection. This scenario requires an appropriate immunosuppressive animal model to understand disease patterns in these patients. Hence, this article reviews the recent advances in the immunosuppressed animal models for chronic HEV infection with emphasis on pathogenesis, immune correlates, and the liver pathology associated with the chronic HEV infections.

Viral Hepatitis: Host Immune Interaction, Pathogenesis and New Therapeutic Strategies

Viral hepatitis is a major cause of liver illness worldwide. Despite advances in the understanding of these infections, the pathogenesis of hepatitis remains a complex process driven by intricate interactions between hepatitis viruses and host cells at the molecular level. This paper will examine in detail the dynamics of these host-pathogen interactions, highlighting the key mechanisms that regulate virus entry into the hepatocyte, their replication, evasion of immune responses, and induction of hepatocellular damage. The unique strategies employed by different hepatitis viruses, such as hepatitis B, C, D, and E viruses, to exploit metabolic and cell signaling pathways to their advantage will be discussed. At the same time, the innate and adaptive immune responses put in place by the host to counter viral infection will be analyzed. Special attention will be paid to genetic, epigenetic, and environmental factors that modulate individual susceptibility to different forms of viral hepatitis. In addition, this work will highlight the latest findings on the mechanisms of viral persistence leading to the chronic hepatitis state and the potential implications for the development of new therapeutic strategies. Fully understanding the complex host-pathogen interactions in viral hepatitis is crucial to identifying new therapeutic targets, developing more effective approaches for treatment, and shedding light on the mechanisms underlying progression to more advanced stages of liver damage.

An Immunocompetent Mongolian Gerbil Model for Hepatitis E Virus Genotype 1 Infection

BACKGROUND & AIMS

Hepatitis E virus (HEV), primarily genotype 1 (HEV-1), causes approximately 20.1 million infections, 44,000 deaths, and 3000 stillbirths annually. Current evidence indicates that HEV-1 is only transmitted in humans. Here, we evaluated whether Mongolian gerbils can serve as animal models for HEV-1 infection.

METHODS

Mongolian gerbils were used for HEV-1 and hepatitis E virus genotype 3 infection experiments. HEV infection parameters, including detection of HEV RNA and HEV antigen, liver function assessment, and histopathology, were evaluated.

RESULTS

We adapted a clinical isolate of HEV-1 for Mongolian gerbils by serial passaging in feces of aged male gerbils. The gerbil-adapted strain obtained at passage 3 induced a robust, acute HEV infection, characterized by stable fecal virus shedding, elevated liver enzymes, histopathologic changes in the liver, and seroconversion to anti-HEV. An infectious complementary DNA clone of the adapted virus was generated. HEV-1-infected pregnant gerbils showed a high rate of maternal mortality and vertical transmission. HEV RNA or antigens were detected in the liver, kidney, intestine, placenta, testis, and fetus liver. Liver and placental transcriptomic analyses indicated activation of host immunity. Tacrolimus prolonged HEV-1 infection, whereas ribavirin cleared infection. The protective efficacy of a licensed HEV vaccine was validated using this model.

CONCLUSIONS

HEV-1 efficiently infected Mongolian gerbils. This HEV-1 infection model will be valuable for investigating hepatitis E immunopathogenesis and evaluating vaccines and antivirals against HEV.

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.

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.

Hepatitis E Virus Genotype 3 among Hemodialysis Patients in Mexico: First Identification of Chronic Infection

The global distribution of hepatitis E virus (HEV) is attributed to its capacity to spread through several routes of transmission; hemodialysis has gained increased amounts of attention in recent years. Although Mexico is considered a hyperendemic region for hepatitis E, no HEV surveillance is performed in the country. The frequency of HEV in hemodialysis (HD) patients has not been determined. Herein, we conducted a cross-sectional single-center analytical study including 67 serum samples from HD patients. Anti-HEV IgG and IgM antibodies and the viral genome were determined; partial regions within the HEV genome were sequenced for further phylogenetic analysis. Globally, 14.9% of the tested patients exhibited reactivity for IgG antibodies against HEV, and none showed reactivity to IgM. A total of 5.9% of the samples showed HEV genome amplification, and sequencing confirmed the identity of genotype 3; subsequent analysis of positive cases revealed two acute cases and chronic hepatitis E infection in one patient. Notably, the chronic patient was negative for anti-HEV IgG antibodies. Our findings highlight the importance of viral genome testing in HD patients and the need to establish guidelines for HEV detection in Mexico.

Exploring the potential of drug repurposing for liver diseases: A comprehensive study

Drug repurposing involves the investigation of existing drugs for new indications. It offers a great opportunity to quickly identify a new drug candidate at a lower cost than novel discovery and development. Despite the importance and potential role of drug repurposing, there is no specific definition that healthcare providers and the World Health Organization credit. Unfortunately, many similar and interchangeable concepts are being used in the literature, making it difficult to collect and analyze uniform data on repurposed drugs. This research was conducted based on understanding general criteria for drug repurposing, concentrating on liver diseases. Many drugs have been investigated for their effect on liver diseases even though they were originally approved (or on their way to being approved) for other diseases. Some of the hypotheses for drug repurposing were first captured from the literature and then processed further to test the hypothesis. Recently, with the revolution in bioinformatics techniques, scientists have started to use drug libraries and computer systems that can analyze hundreds of drugs to give a short list of candidates to be analyzed pharmacologically. However, this study revealed that drug repurposing is a potential aid that may help deal with liver diseases. It provides available or under-investigated drugs that could help treat hepatitis, liver cirrhosis, Wilson disease, liver cancer, and fatty liver. However, many further studies are needed to ensure the efficacy of these drugs on a large scale.

The question of screening organ donors for hepatitis e virus: a case report of transmission by kidney transplantation in France and a review of the literature

BACKGROUND

Hepatitis E is a potentially serious infection in organ recipients, with an estimated two-thirds of cases becoming chronic, and with a subsequent risk of cirrhosis and death. In Europe, transmission occurs most often through the consumption of raw or undercooked pork, more rarely through blood transfusion, but also after solid organ transplantation. Here we describe a case of Hepatitis E virus (HEV) infection transmitted following kidney transplantation and review the literature describing cases of HEV infection transmitted by solid organ transplantation.

CASE PRESENTATION

Three weeks after kidney transplantation, the patient presented with an isolated minimal increase in GGT and hepatic cytolysis 6 months later, leading to the diagnosis of genotype 3c hepatitis E, with a plasma viral load of 6.5 log10IU/mL. In retrospect, HEV RNA was detected in the patient's serum from the onset of hepatitis, and in the donor's serum on the day of donation, with 100% identity between the viral sequences, confirming donor-derived HEV infection. Hepatitis E had a chronic course, was treated by ribavirin, and relapsed 10 months after the end of treatment.

DISCUSSION

Seven cases of transmission of HEV by solid organ transplantation have been described since 2012 without systematic screening for donors, all diagnosed at the chronic infection stage; two patients died. HEV organ donor transmission may be underestimated and there is insufficient focus on immunocompromised patients in whom mild liver function test impairment is potentially related to hepatitis E. However, since HEV infection is potentially severe in these patients, and as evidence accumulates, we believe that systematic screening of organ donors should be implemented for deceased and living donors regardless of liver function abnormalities, as is already the case in the UK and Spain. In January 2024, the French regulatory agency of transplantation has implemented mandatory screening of organ donors for HEV RNA.

Proof of infectivity of hepatitis E virus particles from the ejaculate of chronically infected patients

Recently, hepatitis E virus (HEV, Paslahepevirus balayani) particles were detected for the first time in the ejaculate of two chronically infected patients. Since then, we have been able to detect HEV in ejaculate in five further patients, and thus in a total of seven out of nine (78%) chronically infected men (age 36-67 years, median 56 years). In five patients, the HEV RNA concentration was more than 100-fold higher compared to the serum, while in two patients, the viral load was more than 10-fold lower. However, it has remained unclear whether viral particles shed in the ejaculate were infectious, as a previous cell culture model had failed to demonstrate the infectivity. In the current study, we employed an optimized HEV cell culture system based on overconfluent PLC/PRF/5 cells to investigate the infectivity of HEV particles from ejaculate and other body fluids. With this approach, we were able to show for the first time that HEV particles in the ejaculate from several patients were infectious. HEV replicated to high viral loads of 1e9 HEV RNA copies per ml. This indicates that HEV-positive ejaculate could bear a risk of infection for sexual partners.

Global burden and trends of acute viral hepatitis among children and adolescents from 1990 to 2019: a systematic analysis of the Global Burden of Disease Study 2019

BACKGROUND

Children and adolescents are at high risk for acute viral hepatitis (AVH), but epidemiological research focusing on them has been overshadowed by adult chronic B and C. We provide global, regional, and national estimates of the AVH burden and their trends on people under 20 years from 1990 to 2019.

METHODS

AVH data from Global Burden of Disease Study (GBD) 2019 was used. Incidence and disability-adjusted life years (DALYs) were calculated, analyzing trends with estimated annual percentage change (EAPC) and Joinpoint regression.

RESULTS

In 2019, 156.39 (95% uncertainty interval 145.20-167.16) million new cases of AVH were reported among children and adolescents globally, resulting in 1.98 (1.50-2.55) million DALYs. Incidence rates for young children (< 5 years), older children (5-9 years), and adolescents (10-19 years) were 12,799 (11,068-14,513), 5,108 (4829-5411), and 3020 (2724-3339) per 100,000 population, respectively. The global AVH incidence displayed a linear decline with an EAPC of - 0.66 (- 0.68 to - 0.65). High-incidence regions included sub-Saharan Africa, Oceania, South Asia, and Central Asia, with India, Pakistan, and Nigeria facing the greatest burden. Leading causes were hepatitis A, followed by hepatitis E, B, and C. All hepatitis types showed declining trends, especially hepatitis B. Furthermore, we confirmed the association between the AVH incidence and the socioeconomics, vaccine, and advanced liver diseases.

CONCLUSION

Effective vaccines and treatments for hepatitis B and C offer eradication opportunities. Broadening diagnostic and therapeutic coverage is vital to address disparities in service provision for children and adolescents.

Development and evaluation of a CRISPR-Cas13a system-based diagnostic for hepatitis E virus

OBJECTIVES

Hepatitis E virus (HEV) is the leading cause of acute viral hepatitis worldwide. HEV RNA detection is the gold standard for HEV infection diagnosis and PCR methods are commonly used but are usually time-consuming and expensive, resulting in low detection efficiency and coverage, especially in low-income areas. Here, we developed a simpler and more accessible HEV RNA detection method based on CRISPR-Cas13a system.

METHODS

A total of 265 samples of different types and sources, including 89 positive samples and 176 negative samples, were enrolled for evaluations. The sensitivity and specificity of the Cas13a-crRNA detection system were evaluated. The World Health Organization reference panel for HEV genotypes was used to evaluate the capability for detecting different HEV genotypes. The validity of the assay was compared with RT-qPCR.

RESULTS

The 95 % limits of detection (LOD) of Cas13a-crRNA-based fluorescence assay and strip assay were 12.5 and 200 IU/mL, respectively. They did not show cross-reactivity with samples positive for hepatitis A virus, hepatitis B virus, hepatitis C virus, coxsackievirus A16, rotavirus, enterovirus 71, norovirus or enteropathic Escherichia coli. Different HEV genotypes (HEV1-4) can be detected by the assay. Compared to RT-qPCR, the positive predictive agreements of Cas13a-crRNA-based fluorescence and strip assay were 98.9 % (95 % CI: 93.9-99.8 %) and 91.0 % (95 % CI: 83.3-95.4 %), respectively. The negative predictive agreements were both 100 % (95 % CI: 97.8-100 %).

CONCLUSIONS

In conclusion, we established a rapid and convenient HEV RNA detection method with good sensitivity and specificity based on CRISPR-Cas13a system, providing a new option for HEV infection diagnosis.

The Full-Genome Analysis and Generation of an Infectious cDNA Clone of a Genotype 6 Hepatitis E Virus Variant Obtained from a Japanese Wild Boar: In Vitro Cultivation in Human Cell Lines

Hepatitis E virus (HEV) can cause self-limiting acute and chronic hepatitis infections, particularly in immunocompromised individuals. In developing countries, HEV is mainly transmitted via drinking contaminated water, whereas zoonotic transmission dominates the route of infection in developed countries, including Japan. Pigs are an important reservoir for HEV infection. Wild boars, which share the same genus and species as domestic pigs, are also an HEV reservoir. During our nationwide study of HEV infection in wild boar populations in Japan, a genotype 6 (HEV-6) strain, wbJHG_23, was isolated in Hyogo Prefecture in 2023. The genomic length was 7244 nucleotides, excluding the poly(A) tract. The wbJHG_23 strain exhibited the highest nucleotide identity throughout its genome with two previously reported HEV-6 strains (80.3-80.9%). Conversely, it displayed lower similarity (73.3-78.1%) with the HEV-1-5, HEV-7, and HEV-8 strains, indicating that, although closely related, the wbJHG_23 strain differs significantly from the reported HEV-6 strains and might represent a novel subtype. The wbJHG_23 strain successfully infected the human-derived cancer cell lines, PLC/PRF/5 and A549 1-1H8 cells, suggesting that HEV-6 has the potential for zoonotic infection. An infectious cDNA clone was constructed using a reverse genetics system, and a cell culture system supporting the efficient propagation of the HEV-6 strain was established, providing important tools for further studies on this genotype. Using this cell culture system, we evaluated the sensitivity of the wbJHG_23 strain to ribavirin treatment. Its good response to this treatment suggested that it could be used to treat human infections caused by HEV-6.

The intersection of virus infection and liver disease: A comprehensive review of pathogenesis, diagnosis, and treatment

Liver disease represents a significant global burden, placing individuals at a heightened risk of developing cirrhosis and liver cancer. Viral infections act as a primary cause of liver diseases on a worldwide scale. Infections involving hepatitis viruses, notably hepatitis B, C, and E viruses, stand out as the most prevalent contributors to acute and chronic intrahepatic adverse outcome, although the hepatitis C virus (HCV) can be effectively cured with antiviral drugs, but no preventative vaccination developed. Hepatitis B virus (HBV) and HCV can lead to both acute and chronic liver diseases, including liver cirrhosis and hepatocellular carcinoma (HCC), which are principal causes of worldwide morbidity and mortality. Other viruses, such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV), are capable of causing liver damage. Therefore, it is essential to recognize that virus infections and liver diseases are intricate and interconnected processes. A profound understanding of the underlying relationship between virus infections and liver diseases proves pivotal in the effective prevention, diagnosis, and treatment of these conditions. In this review, we delve into the mechanisms by which virus infections induce liver diseases, as well as explore the pathogenesis, diagnosis, and treatment of liver diseases. This article is categorized under: Infectious Diseases > Biomedical Engineering.

Hepatitis E Virus Infection in Voluntary Blood Donors in the Russian Federation

Transfusion-transmitted hepatitis E virus (HEV) infection is an increasing concern in many countries. We investigated the detection rate of HEV viremia in blood donors in Russia. A total of 20,405 regular repetitive voluntary non-renumerated blood donors from two regions (Moscow and Belgorod) were screened for HEV RNA using the cobas® HEV test in mini-pools of six plasma samples. Samples from each reactive pool were tested individually. The average HEV RNA prevalence was 0.024% (95% CI: 0.01-0.05%), or 1 case per 4081 donations. No statistically significant differences in HEV RNA prevalence were observed between the two study regions. The PCR threshold cycle (Ct) values ranged from 25.0 to 40.5 in reactive pools, and from 20.9 to 41.4 in reactive plasma samples when tested individually. The HEV viremic donors had different antibody patterns. Two donor samples were reactive for both anti-HEV IgM and IgG antibodies, one sample was reactive for anti-HEV IgM and negative for anti-HEV IgG, and two samples were seronegative. At follow-up testing 6 months later, on average, four donors available for follow-up had become negative for HEV RNA and positive for anti-HEV IgG. The HEV ORF2 sequence belonging to HEV-3 sub-genotype 3a was obtained from one donor sample. The sequencing failed in the other four samples from viremic donors, presumably due to the low viral load. In conclusion, the HEV RNA detection rate in blood donors in Russia corresponds with data from other European countries, including those that implemented universal donor HEV screening. These data support the implementation of HEV RNA donor screening to reduce the risk of transfusion-transmitted HEV infection in Russia.

Long-term efficacy of a recombinant hepatitis E vaccine in adults: 10-year results from a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Hepatitis E virus (HEV) is a frequently overlooked causative agent of acute hepatitis. Evaluating the long-term durability of hepatitis E vaccine efficacy holds crucial importance.

METHODS

This study was an extension to a randomised, double-blind, placebo-controlled, phase-3 clinical trial of the hepatitis E vaccine conducted in Dontai County, Jiangsu, China. Participants were recruited from 11 townships in Dongtai County. In the initial trial, a total of 112 604 healthy adults aged 16-65 years were enrolled, stratified according to age and sex, and randomly assigned in a 1:1 ratio to receive three doses of hepatitis E vaccine or placebo intramuscularly at month 0, month 1, and month 6. A sensitive hepatitis E surveillance system including 205 clinical sentinels, covering the entire study region, was established and maintained for 10 years after vaccination. The primary outcome was the per-protocol efficacy of hepatitis E virus vaccine to prevent confirmed hepatitis E occurring at least 30 days after administration of the third dose. Throughout the study, the participants, site investigators, and laboratory staff remained blinded to the treatment assignments. This study is registered with ClinicalTrials.gov (NCT01014845).

FINDINGS

During the 10-year study period from Aug 22, 2007, to Oct 31, 2017, 90 people with hepatitis E were identified; 13 in the vaccine group (0·2 per 10 000 person-years) and 77 in the placebo group (1·4 per 10 000 person-years), corresponding to a vaccine efficacy of 83·1% (95% CI 69·4-91·4) in the modified intention-to-treat analysis and 86·6% (73·0 to 94·1) in the per-protocol analysis. In the subsets of participants assessed for immunogenicity persistence, of those who were seronegative at baseline and received three doses of hepatitis E vaccine, 254 (87·3%) of 291 vaccinees in Qindong at the 8·5-year mark and 1270 (73·0%) of 1740 vaccinees in Anfeng at the 7·5-year mark maintained detectable concentrations of antibodies.

INTERPRETATION

Immunisation with this hepatitis E vaccine offers durable protection against hepatitis E for up to 10 years, with vaccine-induced antibodies against HEV persisting for at least 8·5 years.

FUNDING

National Natural Science Foundation of China, Fujian Provincial Natural Science Foundation, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, and the Fundamental Research Funds for the Central Universities.

Viral hepatitis E: Clinical manifestations, treatment, and prevention

Hepatitis E is a globally distributed infection that varies in seroprevalence between developed and developing regions. In the less developed regions of Asia and Africa, a high seropositivity rate has been reported for hepatitis E virus (HEV) antibodies. Although acute hepatitis E is often self-limited and has a favorable prognosis, some populations experience severe manifestations, which may progress to liver failure. Moreover, some immunocompromised patients are at risk of developing chronic HEV infection and cirrhosis. Proactive screening, reducing misdiagnosis, improving patient management, timely antiviral therapy for severe and chronic cases, and vaccination of high-risk groups are important measures to reduce the morbidity of hepatitis E. This review focused on the clinical presentation, management, and prevention of hepatitis E.

Chronic Hepatitis E Virus Manifesting as Elevated Transaminases in a Heart Transplant Patient

Hepatitis E virus (HEV) is a common cause of viral hepatitis worldwide. Genotypes 1 and 2 cause acute hepatitis in endemic regions (Asia and Africa), whereas genotypes 3 and 4 (America and Europe) result in sporadic acute or chronic hepatitis, specifically in certain groups. HEV infections are rising because of increased transplantation rates and immunosuppression. We report a 75-year-old heart transplant patient with nonspecific symptoms, diagnosed with HEV chronic hepatitis. Despite ribavirin-induced hemolytic anemia, the patient achieved sustained virological response and normalization of liver enzymes.