Hepatitis E virus: Epidemiology, diagnosis, clinical manifestations, and treatment

Genetic substructure and host-specific natural selection trend across vaccine-candidate ORF-2 capsid protein of hepatitis-E virus

Hepatitis E virus is a primary cause of acute hepatitis worldwide. The present study attempts to assess the genetic variability and evolutionary divergence among HEV genotypes. A vaccine promising capsid-protein coding ORF-2 gene sequences of HEV was evaluated using phylogenetics, model-based population genetic methods and principal component analysis. The analyses unveiled nine distinct clusters as subpopulations for six HEV genotypes. HEV-3 genotype samples stratified into four different subgroups, while HEV-4 stratified into three additional subclusters. Rabbit-infectious HEV-3ra samples constitute a distinct cluster. Pairwise analysis identified marked genetic distinction of HEV-4c and HEV-4i subgenotypes compared to other genotypes. Numerous admixed, inter and intragenotype recombinant strains were detected. The MEME method identified several ORF-2 codon sites under positive selection. Some selection signatures lead to amino acid substitutions within ORF-2, resulting in altered physicochemical features. Moreover, a pattern of host-specific adaptive signatures was identified among HEV genotypes. The analyses conclusively depict that recombination and episodic positive selection events have shaped the observed genetic diversity among different HEV genotypes. The significant genetic diversity and stratification of HEV-3 and HEV-4 genotypes into subgroups, as identified in the current study, are noteworthy and may have implications for the efficacy of anti-HEV vaccines.

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.

Rocahepevirus ratti: An underrecognised cause of acute hepatitis

Zoonoses are responsible for many of all emerging infectious diseases as well as for those already established. Rocahepevirus ratti is a rat-originated virus related to the hepatitis E virus (Paslahepevirus balayani) but highly divergent genetically from this, with a high cross-species infection potential and zoonotic transmission. It can infect humans, leading to acute hepatitis, and is primarily transmitted through the consumption of contaminated water. Rocahepevirus ratti was first discovered in Germany in 2010. The first human case was described in 2017 in Hong Kong in an immune-compromised patient. The first case of chronic infection with Rocahepevirus ratti was described in 2023. A meta-analysis based on 38 studies published between 2000 and 2023 identified 21 cases in humans described up to this date and 489 infections in different animals. Raising awareness regarding this virus is essential, as there are probably many cases that remain undiagnosed, and the virus even has the ability to produce chronic infections in selected patients.

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.

Wastewater surveillance for viral pathogens: A tool for public health

A focus on water quality has intensified globally, considering its critical role in sustaining life and ecosystems. Wastewater, reflecting societal development, profoundly impacts public health. Wastewater-based epidemiology (WBE) has emerged as a surveillance tool for detecting outbreaks early, monitoring infectious disease trends, and providing real-time insights, particularly in vulnerable communities. WBE aids in tracking pathogens, including viruses, in sewage, offering a comprehensive understanding of community health and lifestyle habits. With the rise in global COVID-19 cases, WBE has gained prominence, aiding in monitoring SARS-CoV-2 levels worldwide. Despite advancements in water treatment, poorly treated wastewater discharge remains a threat, amplifying the spread of water-, sanitation-, and hygiene (WaSH)-related diseases. WBE, serving as complementary surveillance, is pivotal for monitoring community-level viral infections. However, there is untapped potential for WBE to expand its role in public health surveillance. This review emphasizes the importance of WBE in understanding the link between viral surveillance in wastewater and public health, highlighting the need for its further integration into public health management.

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.

Clinical characteristics and risk factors of Hepatitis E virus infection in Zhejiang Province: a multicenter case-control study

Introduction

Hepatitis E (HE), caused by the Hepatitis E virus (HEV), is a significant cause of acute viral hepatitis globally and a major public health concern, particularly in specific high-prevalence areas in China, which have diverse transmission routes and regional differences. Identifying the primary risk factors for HE transmission is essential to develop targeted interventions for vulnerable populations.

Methods

This study employed a 1:1 matched case-control methodology, using a standardized questionnaire complemented by medical records for data validation.

Results

Among the 442 HE cases and 428 healthy controls, the case group had a higher prevalence of fatigue (46.21%) and loss of appetite (43.84%) compared to the control group. Furthermore, liver function indicators were significantly higher in the case group, with an average alanine aminotransferase (ALT) level of 621.94 U/L and aspartate aminotransferase (AST) level of 411.53 U/L. Severe HE patients were predominantly male, with significantly increased ALT and AST levels reaching 1443.81 U/L and 862.31 U/L respectively, along with a higher incidence of fatigue (90%) and loss of appetite (75%). Multifactorial analysis indicated that frequent dining out (OR = 2.553, 95%CI:1.686-3.868), poor hygiene conditions (OR = 3.889, 95%CI:1.399-10.807), and comorbid chronic illnesses (OR = 2.275, 95%CI:1.616-3.202) were risk factors for HE infection; conversely, good hygiene practices were protective factors against HE infection (OR = 0.698, 95%CI:0.521-0.934).

Conclusion

In conclusion, HE infection in Zhejiang Province is closely associated with dietary habits and environmental hygiene, and individuals with chronic diseases or co-infections are at increased risk. This highlights the need for targeted health education to reduce the incidence of HE among these populations.

Epidemiologic and clinical updates on viral infections in Saudi Arabia

In the past two decades, the world has witnessed devastating pandemics affecting the global healthcare infrastructure and disrupting society and the economy worldwide. Among all pathogens, viruses play a critical role that is associated with outbreaks due to their wide range of species, involvement of animal hosts, easily transmitted to humans, and increased rates of infectivity. Viral disease outbreaks threaten public health globally due to the challenges associated with controlling and eradicating them. Implementing effective viral disease control programs starts with ongoing surveillance data collection and analyses to detect infectious disease trends and patterns, which is critical for maintaining public health. Viral disease control strategies include improved hygiene and sanitation facilities, eliminating arthropod vectors, vaccinations, and quarantine. The Saudi Ministry of Health (MOH) and the Public Health Authority (also known as Weqayah) in Saudi Arabia are responsible for public health surveillance to control and prevent infectious diseases. The notifiable viral diseases based on the Saudi MOH include hepatitis diseases, viral hemorrhagic fevers, respiratory viral diseases, exanthematous viral diseases, neurological viral diseases, and conjunctivitis. Monitoring trends and detecting changes in these viral diseases is essential to provide proper interventions, evaluate the established prevention programs, and develop better prevention strategies. Therefore, this review aims to highlight the epidemiological updates of the recently reported viral infections in Saudi Arabia and to provide insights into the recent clinical treatment and prevention strategies.

Effect and mechanism of C-terminal cysteine on the properties of HEV p222 protein

Preliminary investigations have demonstrated that the cysteines located at the C-terminus of HEV ORF2 protein exhibits disulfide bonding capability during virus-like particles (VLPs) assembly. However, the effect and mechanism underlying the pairing of disulfide bonds formed by C627, C630, and C638 remains unclear. The p222 protein encompasses C-terminus and serves as a representative of HEV ORF2 to investigate the specific impacts of C627, C630, and C638. The three cysteines were subjected to site-directed mutagenesis and expressed in prokaryotes; Both the mutated proteins and p222 underwent polymerization except for p222A; Surprisingly, only p222 was observed as abundant spherical particles under transmission electron microscope (TEM); Stability and immunogenicity of the p222 exhibited higher than other mutated proteins; LC/MS/MS analysis identified four disulfide bonds in the p222. The novel findings suggest that the three cysteines contribute to structural and functional properties of ORF2 protein, highlighting the indispensability of each cysteine.

Progress and Challenges to Hepatitis E Vaccine Development and Deployment

Hepatitis E is a significant cause of acute hepatitis, contributing to high morbidity and mortality rates, and capable of causing large epidemics through fecal-oral transmission. Currently, no specific treatment for hepatitis E has been approved. Given the notably high mortality rate among HEV-infected pregnant women and individuals with underlying chronic liver disease, concerted efforts have been made to develop effective vaccines. The only licensed hepatitis E vaccine worldwide, the HEV 239 (Hecolin) vaccine, has been demonstrated to be safe and efficacious in Phase III clinical trials, in which the efficacy of three doses of HEV 239 remained at 86.6% (95% confidence interval (CI): 73.0-94.1) at the end of 10 years follow-up. In this review, the progress and challenges for hepatitis E vaccines are summarized.

Pathogenesis and clinical features of severe hepatitis E virus infection

The hepatitis E virus (HEV), a member of the Hepeviridae family, is a small, non-enveloped icosahedral virus divided into eight distinct genotypes (HEV-1 to HEV-8). Only genotypes 1 to 4 are known to cause diseases in humans. Genotypes 1 and 2 commonly spread via fecal-oral transmission, often through the consumption of contaminated water. Genotypes 3 and 4 are known to infect pigs, deer, and wild boars, often transferring to humans through inadequately cooked meat. Acute hepatitis caused by HEV in healthy individuals is mostly asymptomatic or associated with minor symptoms, such as jaundice. However, in immunosuppressed individuals, the disease can progress to chronic hepatitis and even escalate to cirrhosis. For pregnant women, an HEV infection can cause fulminant liver failure, with a potential mortality rate of 25%. Mortality rates also rise amongst cirrhotic patients when they contract an acute HEV infection, which can even trigger acute-on-chronic liver failure if layered onto pre-existing chronic liver disease. As the prevalence of HEV infection continues to rise worldwide, highlighting the particular risks associated with severe HEV infection is of major medical interest. This text offers a brief summary of the characteristics of hepatitis developed by patient groups at an elevated risk of severe HEV infection.

An outbreak of hepatitis E virus genotype 4d caused by consuming undercooked pig liver in a nursing home in Zhejiang Province, China

Hepatitis E infection is typically caused by contaminated water or food. In July and August 2022, an outbreak of hepatitis E was reported in a nursing home in Zhejiang Province, China. Local authorities and workers took immediate actions to confirm the outbreak, investigated the sources of infection and routes of transmission, took measures to terminate the outbreak, and summarized the lessons learned. An epidemiological investigation was conducted on all individuals in the nursing home, including demographic information, clinical symptoms, history of dietary, water intake and contact. Stool and blood samples were collected from these populations for laboratory examinations. The hygiene environment of the nursing home was also investigated. A case-control study was conducted to identify the risk factors for this outbreak. Of the 722 subjects in the nursing home, 77 were diagnosed with hepatitis E, for an attack rate of 10.66 %. Among them, 18 (23.38 %, 18/77) individuals had symptoms such as jaundice, fever, and loss of appetite and were defined as the population with hepatitis E. The average age of people infected with hepatitis E virus (HEV) was 59.96 years and the attack rate of hepatitis E among women (12.02 %, 59/491) was greater than that among men (7.79 %, 18/231). The rate was the highest among caregivers (22.22 %, 32/144) and lowest among logistics personnel (6.25 %, 2/32); however, these differences were not statistically significant (P > 0.05). Laboratory sequencing results indicated that the genotype of this hepatitis E outbreak was 4d. A case-control study showed that consuming pig liver (odds ratio (OR) = 7.50; 95 % confidence interval [CI]: 3.84-16.14, P < 0.001) and consuming raw fruits and vegetables (OR = 5.92; 95 % CI: 1.74-37.13, P = 0.017) were risk factors for this outbreak of Hepatitis E. Moreover, a monitoring video showed that the canteen personnel did not separate raw and cooked foods, and pig livers were cooked for only 2 min and 10 s. Approximately 1 month after the outbreak, an emergency vaccination for HEV was administered. No new cases were reported after two long incubation periods (approximately 4 months). The outbreak of HEV genotype 4d was likely caused by consuming undercooked pig liver, resulting in an attack rate of 10.66 %. This was related to the rapid stir-frying cooking method and the hygiene habit of not separating raw and cooked foods.

Systematic review and meta-analysis of hepatitis E seroprevalence in Southeast Asia: a comprehensive assessment of epidemiological patterns

The burden of hepatitis E in Southeast Asia is substantial, influenced by its distinct socio-economic and environmental factors, as well as variations in healthcare systems. The aim of this study was to assess the pooled seroprevalence of hepatitis E across countries within the Southeast Asian region by the UN division.The study analyzed 66 papers across PubMed, Web of Science, and Scopus databases, encompassing data from of 44,850 individuals focusing on anti-HEV seroprevalence. The investigation spanned nine countries, excluding Brunei and East Timor due to lack of data. The pooled prevalence of anti-HEV IgG was determined to be 21.03%, with the highest prevalence observed in Myanmar (33.46%) and the lowest in Malaysia (5.93%). IgM prevalence was highest in Indonesia (12.43%) and lowest in Malaysia (0.91%). The study stratified populations into high-risk (farm workers, chronic patients) and low-risk groups (general population, blood donors, pregnant women, hospital patients). It revealed a higher IgG-28.9%, IgM-4.42% prevalence in the former group, while the latter group exhibited figures of 17.86% and 3.15%, respectively, indicating occupational and health-related vulnerabilities to HEV.A temporal analysis (1987-2023), indicated an upward trend in both IgG and IgM prevalence, suggesting an escalating HEV burden.These findings contribute to a better understanding of HEV seroprevalence in Southeast Asia, shedding light on important public health implications and suggesting directions for further research and intervention strategies.Key pointsResearch QuestionInvestigate the seroprevalence of hepatitis E virus (HEV) in Southeast Asian countries focusing on different patterns, timelines, and population cohorts.FindingsSporadic Transmission of IgG and IgM Prevalence:• Pooled anti-HEV IgG prevalence: 21.03%• Pooled anti-HEV IgM prevalence: 3.49%Seroprevalence among specific groups:High-risk group (farm workers and chronic patients):• anti-HEV IgG: 28.9%• anti-HEV IgM: 4.42%Low-risk group (general population, blood donors, pregnant women, hospital patients):• anti-HEV IgG: 17.86%• anti-HEV IgM: 3.15%Temporal Seroprevalence of HEV:Anti-HEV IgG prevalence increased over decades (1987-1999; 2000-2010; 2011-2023): 12.47%, 18.43%, 29.17% as an anti-HEV IgM prevalence: 1.92%, 2.44%, 5.27%ImportanceProvides a comprehensive overview of HEV seroprevalence in Southeast Asia.Highlights variation in seroprevalence among different population groups.Reveals increasing trend in HEV seroprevalence over the years.Distinguishes between sporadic and epidemic cases for a better understanding of transmission dynamics.

Water-Based Epidemiological Investigation of Hepatitis E Virus in South Africa

Hepatitis E virus (HEV) is an emerging zoonotic pathogen that exhibits great host diversity. The primary means of transmission of the virus in low- and middle-income countries is contaminated water, often due to a lack of access to proper sanitation, which leads to faecal contamination of water sources. Environmental surveillance is an important tool that can be used to monitor virus circulation and as an early warning system for outbreaks. This study was conducted to determine the prevalence and genetic diversity of HEV in wastewater, surface water (rivers and standpipe/ablution water), and effluent from a piggery in South Africa. A total of 536 water samples were screened for HEV using real-time reverse transcription-polymerase chain reaction. Overall, 21.8% (117/536) of the wastewater, river, and ablution water samples tested positive for HEV, whereas 74.4% (29/39) of the samples from the piggery tested positive. Genotyping revealed sequences belonging to HEV genotypes 3 (98%, 53/54) and 4 (2%, 1/54), with subtypes 3c, 3f, and 4b being identified.

Hepatitis E Virus (HEV) Infection Among Immunocompromised Individuals: A Brief Narrative Review

Hepatitis E virus (HEV) is a single-stranded positive-sense RNA virus that belongs to Hepeviridae family. HEV is the most common cause of acute viral hepatitis worldwide. According to the World Health Organization (WHO), there are estimated 20 million HEV infections worldwide every year, leading to estimated 3.3 million symptomatic cases of HEV infection. The WHO estimates that HEV infection caused approximately 44,000 deaths in 2015, which represents 3.3% of mortality rates due to viral hepatitis. In low-income (LI) countries and lower-middle-income (LMI) countries, HEV is a waterborne infection induced by HEV genotype (gt) 1 and HEV gt 2 that cause large outbreaks and affect young individuals with a high mortality rate in pregnant women from South Asian countries and patients with liver diseases. HEV gt 3, HEV gt 4, and HEV gt 7 are responsible for sporadic infections with zoonotic transmission mainly through the consumption of raw or undercooked meat from different animals. Acute HEV infection is relatively asymptomatic or mild clinical form, in rare cases the disease can be moderate/severe clinical forms and result in fulminant hepatitis or acute liver failure (ALF). Furthermore, HEV infection is associated with extrahepatic manifestations, including renal and neurological clinical signs and symptoms. Pregnant women, infants, older people, immunocompromised individuals, patients with comorbidities, and workers who come into close contact with HEV-infected animals are recognized as major risk groups for severe clinical form of HEV infection and fatal outcome. Chronic HEV infection can occur in immunocompromised individuals with the possibility of progression to cirrhosis.

An Acute Infection due to Hepatitis E in the Context of a Patient with Rituximab and Methotrexate Therapy

Background

This report presents the influence of immunosuppression by new rheumatological therapies on hepatitis E virus infection in a 54-year-old male patient with an anti-synthetase syndrome and treatment with methotrexate and rituximab.

Case description

The patient arrived at the Emergency Department with epigastric pain, vomiting and dark urine. Initial examination revealed signs of inflammation and hepatic dysfunction. Subsequent laboratory tests and imaging confirmed acute hepatitis E infection in the context of recent initiation of rituximab therapy. Despite initial suspicion of pancreatitis, subsequent investigations ruled out pancreatic involvement. Treatment with ribavirin, along with supportive measures, led to significant clinical improvement with resolution of jaundice, ascites, and oedema.

Conclusions

This case underscores the importance of considering hepatitis E in patients with autoimmune conditions, especially when initiating immunosuppressive therapies, a situation that is not well described in scientific literature and is increasingly common, necessitating proper recognition.

LEARNING POINTS

Suspect hepatitis E virus infection in the presence of persistent liver failure of unknown cause.Recognise immunosuppression as a cause of increased risk of hepatitis E infection.Take into account the repercussions of immunosuppressive therapy such as rituximab regarding hepatitis E infections in immunocompromised patients.

Monitoring of hepatitis E virus in wastewater can identify clinically relevant variants

Hepatitis E virus (HEV) is prevalent worldwide and can cause persistent infection with severe morbidity. Antiviral treatment approaches can lead to the emergence of viral variants encoding escape mutations that may impede viral clearance. The frequency of these variants remains unknown in the human population as well as environment due to limited comprehensive data on HEV diversity. In this study, we investigated the HEV prevalence and diversity of circulating variants in environmental samples, that is, wastewater and rivers from North-Rhine Westphalia, Germany. HEV prevalence could be determined with 73% of samples tested positive for viral RNA via qRT-PCR. Using high-throughput sequencing, we were able to assess the overall genetic diversity in these samples and identified the presence of clinically relevant variants associated with drug resistance. In summary, monitoring variants from environmental samples could provide valuable insights into estimating HEV prevalence and identifying circulating variants that can impact treatment outcome.

The Risk of Reinfection or Primary Hepatitis E Virus Infection at a Liver Transplant Center in Brazil: An Observational Cohort Study

The hepatitis E virus is a major etiological agent of chronic hepatitis in immunosuppressed individuals. Seroprevalence in the liver transplantation setting varies according to the seroprevalence of the general population in different countries. This was a prospective cohort study of liver transplant recipients in southeastern Brazil. Recipients were systematically followed for one year, with the objective of determining the prevalence, incidence, and natural history of HEV infection in this population. We included 107 liver transplant recipients and 83 deceased donors. Positivity for anti-HEV IgG was detected in 10.2% of the recipients and in 9.7% of the donors. None of the patients tested positive for HEV RNA at baseline or during follow-up. There were no episodes of reactivation or seroconversion, even in cases of serological donor-recipient mismatch or in recipients with acute hepatitis. Acute and chronic HEV infections seem to be rare events in the region studied. That could be attributable to social, economic, and environmental factors. Our data indicate that, among liver transplant recipients, hepatitis E should be investigated only when there are elevated levels of transaminases with no defined cause, as part of the differential diagnosis of seronegative hepatitis after transplantation.

Hepatitis E virus infections among patients with acute febrile jaundice in two regions of Cameroon: First molecular characterization of hepatitis E virus genotype 4

BACKGROUND

Febrile jaundice is a common indicator of certain infectious diseases, including hepatitis E. In Cameroon, the yellow fever virus is the only pathogen that is monitored in patients who present with this symptom. However, more than 90% of the samples received as part of this surveillance are negative for yellow fever. This study aimed to describe the prevalence and hepatitis E virus (HEV) genotype among yellow fever-negative patients in the Far North and West regions of Cameroon.

METHODS

In a cross-sectional study, yellow fever surveillance-negative samples collected between January 2021 and January 2023 were retrospectively analyzed. Anti-HEV IgM and IgG antibodies were tested using commercially available ELISA kits. Anti-HEV IgM and/or IgG positive samples were tested for HEV RNA by real-time RT-PCR, followed by nested RT-PCR, sequencing and phylogenetic analysis.

RESULTS

Overall, 121 of the 543 samples (22.3%, 95% CI: 19.0% - 26.0%) were positive for at least one anti-HEV marker. Amongst these, 8.1% (44/543) were positive for anti-HEV IgM, 5.9% (32/543) for anti-HEV IgG, and 8.3% (45/544) for both markers. A total of 15.2% (12/79) samples were positive for HEV RNA real-time RT-PCR and 8 samples were positive for HEV RNA by nested RT-PCR. Phylogenetic analysis showed that the retrieved sequences clustered within HEV genotypes/subtypes 1/1e, 3/3f and 4/4b.

CONCLUSION

Our results showed that HEV is one of the causes of acute febrile jaundice in patients enrolled in the yellow fever surveillance program in two regions of Cameroon. We described the circulation of three HEV genotypes, including two zoonotic genotypes. Further studies will be important to elucidate the transmission routes of these zoonotic HEV genotypes to humans in Cameroon.

Seroprevalence of the Hepatitis E Virus in Indigenous and Non-Indigenous Communities from the Brazilian Amazon Basin

Hepatitis E virus (HEV) infection is a common cause of acute viral hepatitis in tropical regions. In Brazil, HEV G3 is the only genotype detected to date. Reports on HEV prevalence are heterogeneous. We aimed to compare the prevalence of anti-HEV among three populations living in the Brazilian Amazon basin. Two cross-sectional studies were conducted in urban, rural, and Yanomami indigenous areas. Plasma samples from 428 indigenous and 383 non-indigenous subjects were tested for anti-HEV IgG using enzyme-linked immunosorbent assays. The overall prevalence of anti-HEV was 6.8% (95%CI: 5.25-8.72), with 2.8% (12/428) found in the Yanomami areas, 3% (3/101) in an urban area, and 14.2% (40/282) in a rural area. Multivariate logistic analysis indicated that patients aged 31-45 years or ≥46 years are more likely to present anti-HEV positivity, with a respective aOR of 2.76 (95%CI: 1.09-7.5) and 4.27 (95%CI: 1.58-12.35). Furthermore, residence in a rural area (aOR: 7.67; 95%CI: 2.50-33.67) represents a relevant risk factor for HEV infection. Additional studies detecting HEV RNA in fecal samples from both humans and potential animal reservoirs are necessary to comprehensively identify risk factors associated with HEV exposure.

Pet safety guidelines for pediatric transplant recipients

Approximately 70% (90.5 million) of United States (US) households own at least one pet. Dogs are the most common, making up about 38% of all household pets, followed by cats, which make up 25%. Other pets such as fish, birds, reptiles, and small animals such as hamsters, gerbils, and rabbits are less common household members. Pets are often considered a part of the family and there are significant medical and psychosocial benefits to pet ownership; however, the possibility of disease transmission exists related to the type of animal and infectious organism, and specific human risk factors. Immunocompromised individuals may be at increased risk of serious illness from zoonotic infections. During the transplant evaluation and routinely posttransplant, the multidisciplinary team should inquire about pet ownership and animal exposures to guide on potential risks. This review discusses the most common diseases seen in various household pets including dogs, cats, birds, fish, and some farm animals. We will also present guidelines for pet safety and include strategies to decrease the risk of infection while supporting the benefits of pet ownership after transplant.

Development of a Sensitive and Specific Quantitative RT-qPCR Method for the Detection of Hepatitis E Virus Genotype 3 in Porcine Liver and Foodstuff

As an international and zoonotic cause of hepatitis, hepatitis E virus (HEV) poses a significant risk to public health. However, the frequency of occurrence and the degree of contamination of food of animal origin require further research. The aim of this study was to develop and validate a highly sensitive quantitative RT-qPCR assay for the detection and quantification of HEV contamination in porcine liver and food. The focus was on genotype 3, which is most common as a food contaminant in developed countries and Europe. The selected assay has its target sequence in the open reading frame 1 (ORF1) of the HEV genome and showed good results in inclusivity testing, especially for HEV genotype 3. The developed assay seems to show high efficiency and a low intercept when compared to other assays, while having a comparable limit of detection (LOD). In addition, a standard curve was generated using artificially spiked liver to provide more accurate quantitative results for contamination assessment and tracking in this matrix. Application of the assay to test 67 pig livers from different origins resulted in a positivity rate of 7.5%, which is consistent with the results of numerous other prevalence studies. Quantitative detection of the viral genome in the food chain, particularly in pig livers, is essential for understanding the presence and evolution of HEV contamination and thus ensures consumer safety.

Hepatitis E infection: A review

Hepatitis E virus (HEV) is a small non-enveloped virus that is transmitted via the fecal-oral route. It is a highly common cause of acute hepatitis, particularly in low to middle income regions of Asia, Africa, and Central America. Most cases are self-limited, and symptomatic patients usually present with acute icteric hepatitis. A subset of patients including pregnant women, older men, those with pre-existing liver disease and immunocompromised patients however, may develop severe disease and hepatic failure. Immunocompromised patients are also at risk for chronic infection, and their immunosuppression should be decreased in order to facilitate viral clearance. HEV can also present with a variety of extra-intestinal manifestations including neurological, renal, hematological, and pancreatic derangements. The gold standard of diagnosis is HEV ribonucleic acid detection via nucleic acid amplification testing. Currently, there are no approved treatments for Hepatitis E, though ribavirin is the most commonly used agent to reduce viral load. Studies assessing the safety and efficacy of other antiviral agents for HEV are currently underway. HEV vaccination has been approved in China, and is currently being investigated in other regions as well. This review article aims to discuss the epidemiology, pathogenesis, presentation, diagnosis, complications, and treatment of Hepatitis E infection.

Plasma metagenomics reveals regional variations of emerging and re-emerging pathogens in Chinese blood donors with an emphasis on human parvovirus B19

At present, many infectious pathogens, especially emerging/re-emerging pathogens, exist in the blood of voluntary blood donors and may be transmitted through blood transfusions. However, most of Chinese blood centers only routinely screen for HBV, HCV, HIV, and syphilis. We employed metagenomic next-generation sequencing (mNGS) to investigate the microbiome in healthy voluntary blood donors to help assess blood safety in China by identifying infectious pathogens presented in donations that could lead to transfusion-acquired infections. We collected 10,720 plasma samples from voluntary blood donors from seven blood centers in different cities during 2012-2018 in China. A total of 562 GB of clean data was obtained. By analyzing the sequencing data, it was found that the most commonly identified bacteria found in the healthy blood were Serratia spp. (5.0176%), Pseudomonas spp. (0.6637%), and Burkholderia spp. (0.5544%). The principal eukaryote were Leishmania spp (1.3723%), Toxoplasma gondii (0.6352%), and Candida dubliniensis (0.1848%). Among viruses, Human Parvovirus B19 (B19V) accounts for the highest proportion (0.1490%), followed by Torque teno midi virus (0.0032%) and Torque teno virus (0.0015%). Since that B19V is a non-negligible threat to blood safety, we evaluated the positive samples for B19V tested by mNGS using quantitative polymerase chain reaction, Sanger sequencing, and phylogenetic analysis to achieve a better understanding of B19V in Chinese blood donors. Subsequently, 9 (0.07%) donations were positive for B19V DNA. The quantitative DNA levels ranged from 5.58 × 10² to 7.24 × 10⁴ IU/ml. The phylogenic analyses showed that prevalent genotypes belonged to the B19-1A subtype, which disclosed previously unknown regional variability in the B19V positivity rate. The investigation revealed that many microbes dwell in the blood of healthy donors, including some pathogens that may be dormant in the blood and only cause disease under specific conditions. Thus, investigating the range and nature of potential pathogens in the qualified donations provided a framework for targeted interventions to help prevent emerging and re-emerging infectious diseases.

Dysregulated metabolites and lipids in serum of patients with acute hepatitis E: A longitudinal study

Hepatitis E is a disease associated with acute inflammation of the liver. It is related to several dysregulated metabolic pathways and alterations in the concentration of several metabolites. However, longitudinal analysis of the alterations in metabolites and lipids is generally lacking. This study investigated the changes in levels of metabolites and lipids over time in sera from men with acute hepatitis E compared to healthy controls similar in age and gender. Untargeted measurement of levels of various metabolites and lipids was done using mass spectrometry on 65 sera sequentially sampled from 14 patients with acute hepatitis E and 25 serum samples from five controls. Temporal changes in intensities of metabolites and lipids were determined over different times at 3-day periods for the hepatitis E virus (HEV) group. In carbohydrate metabolism, glucose levels, fructose 1-6-bisphosphate and ribulose-5-phosphate were increased in the HEV-infected persons compared to the healthy controls. HEV infection is significantly associated with decreased levels of inosine, guanosine, adenosine and urate in purine metabolism and thymine, uracil and β-aminoisobutyrate in pyrimidine metabolism. Glutamate, alanine and valine levels were significantly lower in the HEV group than in healthy individuals. Homogentisate of tyrosine metabolism and cystathionine of serine metabolism were increased, whereas kynurenate of tryptophan metabolism decreased in the HEV group. Metabolites of the bile acid biosynthesis, urea cycle (arginine and citrulline) and ammonia recycling (urocanate) were significantly altered. Co-enzymes, pantothenate and pyridoxal, and co-factors, lipoamide and FAD, were elevated in the HEV group. The acylcarnitines, sphingomyelins, phosphatidylcholine (PC), phosphatidylethanolamine (PE), lysoPC and lysoPE tended to be lower in the HEV group. In conclusion, acute hepatitis E is associated with altered metabolite and lipid profiles, significantly increased catabolism of carbohydrates, purines/pyrimidines and amino acids, and decreased levels of several glycerophospholipids.

Point-of-Care Testing for Hepatitis Viruses: A Growing Need

Viral hepatitis, caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV), is a major global public health problem. These viruses cause millions of infections each year, and chronic infections with HBV, HCV, or HDV can lead to severe liver complications; however, they are underdiagnosed. Achieving the World Health Organization's viral hepatitis elimination goals by 2030 will require access to simpler, faster, and less expensive diagnostics. The development and implementation of point-of-care (POC) testing methods that can be performed outside of a laboratory for the diagnosis of viral hepatitis infections is a promising approach to facilitate and expedite WHO's elimination targets. While a few markers of viral hepatitis are already available in POC formats, tests for additional markers or using novel technologies need to be developed and validated for clinical use. Potential methods and uses for the POC testing of antibodies, antigens, and nucleic acids that relate to the diagnosis, monitoring, or surveillance of viral hepatitis infections are discussed here. Unmet needs and areas where additional research is needed are also described.

Hepatitis E virus neutralization by porcine serum antibodies

The consumption of raw or undercooked meat products poses a serious risk for human hepatitis E virus (HEV) infections. In many high-income countries, domestic pigs and wild boars represent the main animal reservoirs for HEV and are usually identified by reverse transcription-PCR and antibody enzyme-linked immunosorbent assay (ELISA). In order to characterize the humoral immune response in more detail, a cell culture-based serum neutralization assay using a culture-adapted HEV strain was established here. Measurement of neutralizing antibodies was only possible after removing the viral quasi-envelope by detergent treatment. Serum samples of 343 wild boars from Northern Germany were first analyzed for anti-HEV IgG using an in-house ELISA, resulting in 19% positive samples. Subsequently, a subset of 41 representative samples was tested with the neutralization assay, and the results correlated well with those obtained by ELISA. Not only the human HEV strain 47832c but also two porcine HEV strains were shown to be neutralized by porcine serum antibodies. Neutralizing activity was also found in samples containing both HEV-specific antibodies and HEV RNA. Testing of serum samples derived from two experimentally infected domestic pigs showed a steep increase in neutralizing activity at 24 or 51 days post infection, dependent on the used infectious dose. The developed assay can be useful for characterization of the humoral immune response after HEV infection and for assessing the efficiency of HEV vaccine candidates.

Acute Hepatitis E-Associated Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is a rare autoimmune disorder of the peripheral nervous system that causes progressive weakness and sensory disturbances, usually following an infection or immunization. It has been associated with multiple causes, including bacterial and viral infections. Hepatitis E virus (HEV) is a common cause of acute viral hepatitis that can rarely develop neurological complications. We report a case of a 72-year-old man who developed GBS secondary to an acute HEV infection. He presented with numbness and weakness of the lower limbs that rapidly evolved into respiratory failure requiring mechanical ventilation and intravenous immunoglobulin therapy (IVIg). This case adds to the literature on the association between HEV infection and GBS and the importance of early detection of this rapidly progressive condition.

An Update in Knowledge of Pigs as the Source of Zoonotic Pathogens

The available data indicate that the human world population will constantly grow in the subsequent decades. This constant increase in the number of people on the Earth will lead to growth in food demand, especially in food of high nutritional value. Therefore, it is expected that the world livestock population will also increase. Such a phenomenon enhances the risk of transmitting pathogens to humans. As pig production is one of the most significant branches of the world's livestock production, zoonoses of porcine origins seem to be of particular importance. Therefore, in this review, we aim to introduce the latest data concerning, among other things, epidemiology and available preventive measures to control the most significant porcine zoonoses of viral, bacterial, and parasitic origin.

Hepatitis E Virus in Livestock-Update on Its Epidemiology and Risk of Infection to Humans

Hepatitis E virus (HEV) is a public health problem worldwide and an important food pathogen known for its zoonotic potential. Increasing numbers of infection cases with human HEV are caused by the zoonotic transmission of genotypes 3 and 4, mainly by consuming contaminated, undercooked or raw porcine meat. Pigs are the main reservoir of HEV. However, it should be noted that other animal species, such as cattle, sheep, goats, and rabbits, may also be a source of infection for humans. Due to the detection of HEV RNA in the milk and tissues of cattle, the consumption of infected uncooked milk and meat or offal from these species also poses a potential risk of zoonotic HEV infections. Poultry infected by avian HEV may also develop symptomatic disease, although avian HEV is not considered a zoonotic pathogen. HEV infection has a worldwide distribution with different prevalence rates depending on the affected animal species, sampling region, or breeding system.

A multispecies competitive nanobody-based ELISA for the detection of antibodies against hepatitis E virus

The hepatitis E virus (HEV) is an emergent zoonotic virus causing viral hepatitis worldwide. Clinically, hepatitis E is not easily distinguished from other types of acute viral hepatitis. There is a need for HEV diagnostic assays to detect and prevent interspecies transmission among susceptible populations. Nanobodies (Nbs) are expressed recombinantly in different systems, produced with high yields, and have superior physicochemical properties compared with conventional antibodies (Ab). Several Nbs against ORF2, the capsid protein and main antigen, were selected and produced in E. coli. Nb39 and Nb74 specifically recognized HEV ORF2 (genotypes 3 and 4). A competitive ELISA (cELISA) was developed and validated using a reference panel of human (n = 86) and swine sera (n = 116) tested in comparison with a commercial kit. The optimal cutoff values determined by ROC analysis were 69.16% (human) and 58.76% (swine); the sensitivity and specificity were high: 97.4% (95% CI 86.5-99.5%) and 95.8% (95% CI 86.0-98.8%) for human vs. 100% (95% CI 93.5-100%) and 98.3% (95% CI 91.0-99.7%) for swine. Further, the cELISA detected total anti-HEV antibodies in wild boar, deer, and mice. To our knowledge, this is the first report of production of Nbs against HEV-3 ORF2 for diagnostic purposes.

A Comparison of Clinical Manifestations and Outcomes between Acute Sporadic Hepatitis A and Hepatitis E Infections in Thailand

Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections often present as acute hepatitis with prodromal symptoms. These infections, transmitted via the oral-enteral route, constitute significant public health challenges, particularly in developing countries with subpar sanitary systems. The aim of the study was to describe the clinical manifestations, laboratory findings, and outcomes of hepatitis A and hepatitis E infections in Thailand. We conducted a retrospective chart review and analysis of 152 patients diagnosed with acute hepatitis A or hepatitis E from January 2007 to August 2018 at Siriraj Hospital. The hepatitis E cohort was older with a greater prevalence of comorbidities (hypertension, diabetes mellitus, chronic kidney disease, chronic hepatitis B, and post-kidney transplantation status) than the hepatitis A cohort. While the majority of hepatitis A patients presented with fever (98%) and jaundice (96%), these symptoms were less pronounced in hepatitis E patients. Furthermore, hepatitis A patients exhibited significantly higher aminotransferase and total bilirubin levels. However, clinical outcomes, such as hospitalization rates, progression to acute liver failure, and mortality, were comparable across both groups. In conclusion, although the clinical manifestations of hepatitis A and hepatitis E were similar, fever and jaundice were more prevalent and aminotransferase and bilirubin levels were higher in the HAV-infected group.

Seroprevalence of emerging hepatitis E virus in patients with acute hepatitis between 2004 and 2018 in Csongrád County, Hungary

OBJECTIVES

Hepatitis E virus (HEV) has recently become endemic in Europe, however, it is often a remnant neglected by clinicians as the causative agent of acute and chronic hepatitis and is often misdiagnosed as a drug-induced liver injury. The infection rate in European pig farms is estimated to be around 15-20%, therefore, the primary source of HEV infections might be poorly prepared pork meat. As HEV infections may occur more often in clinical practice than previously thought, the present paper aims to analyse the seroprevalence of HEV in patients with acute hepatitis over a period of 14 years in Csongrád County, Hungary.

METHODS

The sera of 4,270 hepatitis patients collected between 2004-2018 were tested for cumulative anti-HEV IgG/IgM. Furthermore, 170 IgM positive sera were tested for the presence of viral RNA by RT-qPCR.

RESULTS

Between 2012-2018, the cumulative seroprevalence has increased 9.18 times, and between 2013-2018, IgM prevalence has increased 12.49 times. Viral RNA was detectable in 12.35% of IgM positive sera.

CONCLUSION

The present paper presents data showing that the seroprevalence of hepatitis E virus has increased markedly over the course of the last decade in Hungary and in other European countries as well. The exact reason behind this phenomenon is yet to be determined. To assess the dynamics and the reason for this increase in prevalence, pan-European, multicentre studies should be conducted.

Epidemiology of Suspected and Confirmed Acute Hepatitis E Cases Reported Among Los Angeles County Residents, 2017-2019

In a 3-year period, 38 of 48 persons testing positive for hepatitis E virus (HEV) immunoglobulin M in Los Angeles County did not meet the acute HEV case definition. Healthcare providers should restrict HEV serologic testing for persons with clinically compatible symptoms or epidemiologic risk factors.

Analysis of the spatial-temporal distribution characteristics of hepatitis E in Jiangsu province from 2005 to 2020

Objective

This study attempts to analyze the spatial clustering and spatial-temporal distribution characteristics of hepatitis E (HE) at the county (city and district) level in Jiangsu province to provide a scientific basis for the prevention and control of HE.

Method

The information on HE cases reported in the Chinese Center for Disease Control and Prevention Information System from 2005 to 2020 was collected for spatial autocorrelation analysis and spatial-temporal clustering analysis.

Result

From 2005 to 2020, 48,456 HE cases were reported in Jiangsu province, with an average annual incidence rate of 3.87/100,000. Male cases outnumbered female cases (2.46:1), and the incidence was highest in the 30-70 years of age group (80.50%). Farmers accounted for more than half of all cases (59.86%), and in terms of the average annual incidence, the top three cities were all in Zhenjiang city. Spatial autocorrelation analysis showed that Global Moran's I of HE incidence varied from 0.232 to 0.513 for the years. From 2005 to 2020, 31 counties (cities and districts) had high and statistically significant HE incidence, and two clustering areas were detected by spatial-temporal scanning.

Conclusion

HE incidence in Jiangsu province from 2005 to 2020 was stable, with age and gender differences, regional clustering, and spatial-temporal clustering. Further investigation of HE clustering areas is necessary to formulate corresponding targeted prevention and control measures.

Effect of High Hydrostatic Pressure Processing and Holder Pasteurization of Human Milk on Inactivation of Human Coronavirus 229E and Hepatitis E Virus

In preterm infants, sterilized donor milk (DM) is frequently used for feeding when breast milk is lacking. Most human milk banks use the Holder pasteurization method (HoP) to ensure the microbiological safety of DM. However, this method degrades many bioactive factors and hormones. Recently, high hydrostatic pressure (HHP) processing, which preserves bioactive factors in human milk, has been proposed as an alternative method to ensure the safety of DM. Although HHP treatment has been shown to be effective for viral inactivation, the effect of HHP on viruses that may be present in the complex nutritional matrix of human milk has not yet been defined. In the present study, we compared the efficacy of two HHP protocols (4 cycles at 350 MPa at 38 °C designated as 4xHP350 treatment, and 1 cycle at 600 MPa at 20 °C designated as 1xHP600 treatment) with the HoP method on artificially virus-infected DM. For this purpose, we used human coronavirus 229E (HCoV-229E) and hepatitis E virus (HEV) as surrogate models for enveloped and non-enveloped viruses. Our results showed that HCoV-229E is inactivated by HHP and HoP treatment. In particular, the 4xHP350 protocol is highly effective in inactivating HCoV-229E. However, our results demonstrated a matrix effect of human milk on HCoV-229E inactivation. Furthermore, we demonstrated that HEV is stable to moderate pressure HHP treatment, but the milk matrix does not protect it from inactivation by the high-pressure HHP treatment of 600 MPa. Importantly, the complex nutritional matrix of human milk protects HEV from inactivation by HoP treatment. In conclusion, we demonstrated that HHP and HoP treatments do not lead to complete inactivation of both surrogate virus models, indicating that these treatments cannot guarantee total viral safety of donor milk.

The Re-Emergence of Hepatitis E Virus in Europe and Vaccine Development

Hepatitis E virus (HEV) is one of the leading causes of acute viral hepatitis. Transmission of HEV mainly occurs via the fecal-oral route (ingesting contaminated water or food) or by contact with infected animals and their raw meat products. Some animals, such as pigs, wild boars, sheep, goats, rabbits, camels, rats, etc., are natural reservoirs of HEV, which places people in close contact with them at increased risk of HEV disease. Although hepatitis E is a self-limiting infection, it could also lead to severe illness, particularly among pregnant women, or chronic infection in immunocompromised people. A growing number of studies point out that HEV can be classified as a re-emerging virus in developed countries. Preventative efforts are needed to reduce the incidence of acute and chronic hepatitis E in non-endemic and endemic countries. There is a recombinant HEV vaccine, but it is approved for use and commercially available only in China and Pakistan. However, further studies are needed to demonstrate the necessity of applying a preventive vaccine and to create conditions for reducing the spread of HEV. This review emphasizes the hepatitis E virus and its importance for public health in Europe, the methods of virus transmission and treatment, and summarizes the latest studies on HEV vaccine development.

Hepatitis E virus seroprevalence among employees in catering and public place industries in Nanjing, China

This study aimed to assess the prevalence of anti-hepatitis E virus (HEV) immunoglobulin (Ig) M and elevated serum alanine aminotransferase (ALT) levels among employees in catering and public place industries. Blood samples were collected between January and December 2020 from 26,790 employees working in the Qinhuai district of Nanjing, China. Anti-HEV IgM in the serum samples was tested by the capture ELISA method and ALT was tested by the IFCC method. Samples positive for anti-HEV IgM or with ALT levels over 200 U/L were subjected to PCR screening of HEV RNA. The overall seroprevalence of anti-HEV IgM was 0.41%, and the seroprevalence was slightly higher in males (0.47%) than in females (0.37%); however, the difference was not substantial (p = 0.177). Seroprevalence of anti-HEV IgM increased with age, reaching its peak level after 48 years of age. The prevalence of elevated ALT levels was 4.24%, and males exhibited a higher prevalence than females (6.78% vs 2.65%, p < 0.001). Prevalence of elevated ALT levels differed in age groups and the 26-36-year-old group had the highest rate of elevated ALT levels. Employees with elevated ALT levels had a higher prevalence of positive anti-HEV IgM than those with normal ALT (0.57% vs 0.31%, p < 0.001). Positive HEV RNA was detected in one anti-HEV IgM-negative employee with ALT higher than 200 U/L. In our study, all the HEV RNA-positive and IgM-positive individuals are asymptomatic, and a combination of ALT tests, serological methods, and molecular methods is recommended to screen asymptomatic HEV carriers and reduce the risk of transmission.

Genotype 4 Hepatitis E virus replicates in the placenta, causes severe histopathological damage, and vertically transmits to fetuses

BACKGROUND

Hepatitis E virus (HEV) infection in pregnant women causes adverse pregnancy outcomes, including maternal death, premature delivery, stillbirth, and fetal infection. However, the pathogenesis of maternal and fetal HEV infection is unclear.

METHODS

Placenta and placental appendixes were collected from HEV-4 infected pregnant women to explore the vertical transmission of HEV from mothers to fetuses.

RESULTS

HEV-4 replicated in the placenta, placental membrane, and umbilical cord and was vertically transmitted from mothers to fetuses. HEV-4 placental infection resulted in serious histopathological damage, such as fibrosis and calcification, and severe inflammatory responses. Adverse maternal outcomes were observed in 38.5% of HEV-4 infected pregnant women. The distinct cytokine/chemokine expression patterns of HEV-infected pregnant women and nonpregnant women may contribute to the adverse pregnancy outcomes. Furthermore, the impaired maternal and fetal innate immune responses against HEV-4 facilitated viral replication during pregnancy.

CONCLUSION

HEV-4 replicates in the placenta and is vertically transmitted from mothers to fetuses, causing severe histopathological damage.

Risk Factors for Hepatitis E Virus Infection and Eating Habits in Kidney Transplant Recipients

There is a significant risk for ongoing and treatment-resistant courses of hepatitis E virus (HEV) infection in patients after solid organ transplantation. The aim of this study was to identify risk factors for the development of hepatitis E, including the dietary habits of patients. We conducted a retrospective single-center study with 59 adult kidney and combined kidney transplant recipients who were diagnosed with HEV infection between 2013 and 2020. The outcomes of HEV infections were analyzed during a median follow-up of 4.3 years. Patients were compared with a control cohort of 251 transplant patients with elevated liver enzymes but without evidence of an HEV infection. Patients' alimentary exposures during the time before disease onset or diagnosis were assessed. Previous intense immunosuppression, especially treatment with high-dose steroids and rituximab, was a significant risk factor to acquire hepatitis E after solid organ transplantation. Only 11 out of 59 (18.6%) patients reached remission without further ribavirin (RBV) treatment. A total of 48 patients were treated with RBV, of which 19 patients (39.6%) had either viral rebounds after the end of treatment or did not reach viral clearance at all. Higher age (>60 years) and a BMI ≤ 20 kg/m² were risk factors for RBV treatment failure. Deterioration in kidney function with a drop in eGFR (p = 0.046) and a rise in proteinuria was more common in patients with persistent hepatitis E viremia. HEV infection was associated with the consumption of undercooked pork or pork products prior to infection. Patients also reported processing raw meat with bare hands at home more frequently than the controls. Overall, we showed that the intensity of immunosuppression, higher age, a low BMI and the consumption of undercooked pork meat correlated with the development of hepatitis E.

The prevention strategies of swine viruses related to xenotransplantation

Xenotransplantation is considered a solution for the shortage of organs, and pigs play an indispensable role as donors in xenotransplantation. The biosecurity of pigs, especially the zoonotic viruses carried by pigs, has attracted attention. This review introduces several viruses, including porcine endogenous retroviruses that are integrated into the pig genome in a DNA form, herpesviruses that have been proven to clearly affect recipient survival time in previous xenotransplant surgeries, the zoonotic hepatitis E virus, and the widely distributed porcine circoviruses. The detail virus information, such as structure, caused diseases, transmission pathways, and epidemiology was introduced in the current review. Diagnostic and control measures for these viruses, including detection sites and methods, vaccines, RNA interference, antiviral pigs, farm biosecurity, and drugs, are discussed. The challenges faced, including those posed by other viruses and newly emerged viruses, and the challenges brought by the modes of transmission of the viruses are also summarized.

Systematic review of global hepatitis E outbreaks to inform response and coordination initiatives

INTRODUCTION

Hepatitis E virus (HEV) is the most common cause of acute hepatitis. While symptoms are generally mild and resolve within weeks, some populations (e.g., pregnant women, immunocompromised adults) are at high-risk of severe HEV-related morbidity and mortality. There has not been a recent comprehensive review of contemporary HEV outbreaks, which limits the validity of current disease burden estimates. Therefore, we aimed to characterize global HEV outbreaks and describe data gaps to inform HEV outbreak prevention and response initiatives.

METHODS

We performed a systematic review of peer-reviewed (PubMed, Embase) and gray literature (ProMED) to identify reports of outbreaks published between 2011 and 2022. We included (1) reports with ≥ 5 cases of HEV, and/or (2) reports with 1.5 times the baseline incidence of HEV in a specific population, and (3) all reports with suspected (e.g., clinical case definition) or confirmed (e.g., ELISA or PCR test) cases if they met criterium 1 and/or 2. We describe key outbreak epidemiological, prevention and response characteristics and major data gaps.

RESULTS

We identified 907 records from PubMed, 468 from Embase, and 247 from ProMED. We screened 1,362 potentially relevant records after deduplication. Seventy-one reports were synthesized, representing 44 HEV outbreaks in 19 countries. The populations at risk, case fatalities, and outbreak durations were not reported in 66% of outbreak reports. No reports described using HEV vaccines. Reported intervention efforts included improving sanitation and hygiene, contact tracing/case surveillance, chlorinating boreholes, and advising residents to boil water. Commonly missing data elements included specific case definitions used, testing strategy and methods, seroprevalence, impacts of interventions, and outbreak response costs. Approximately 20% of HEV outbreaks we found were not published in the peer-reviewed literature.

CONCLUSION

HEV represents a significant public health problem. Unfortunately, extensive data shortages and a lack of standardized reporting make it difficult to estimate the HEV disease burden accurately and to implement effective prevention and response activities. Our study has identified major gaps to guide future studies and outbreak reporting systems. Our results support the development of standardized reporting procedures/platforms for HEV outbreaks to ensure accurate and timely data distribution, including active and passive coordinated surveillance systems, particularly among high-risk populations.

Alterations of the gut microbiota associated with the occurrence and progression of viral hepatitis

Background

Gut microbiota is the largest population of microorganisms and is closely related to health. Many studies have explored changes in gut microbiota in viral hepatitis. However, the correlation between gut microbiota and the occurrence and progression of viral hepatitis has not been fully clarified.

Methods

PubMed and BioProject databases were searched for studies about viral hepatitis disease and 16S rRNA gene sequencing of gut microbiota up to January 2023. With bioinformatics analyses, we explored changes in microbial diversity of viral hepatitis, screened out crucial bacteria and microbial functions related to viral hepatitis, and identified the potential microbial markers for predicting risks for the occurrence and progression of viral hepatitis based on ROC analysis.

Results

Of the 1389 records identified, 13 studies met the inclusion criteria, with 950 individuals including 656 patient samples (HBV, n = 546; HCV, n = 86; HEV, n = 24) and 294 healthy controls. Gut microbial diversity is significantly decreased as the infection and progression of viral hepatitis. Alpha diversity and microbiota including Butyricimonas, Escherichia-Shigella, Lactobacillus, and Veillonella were identified as the potential microbial markers for predicting the risk of development of viral hepatitis (AUC>0.7). Microbial functions including tryptophan metabolism, fatty acid biosynthesis, lipopolysaccharide biosynthesis, and lipid metabolism related to the microbial community increased significantly as the development of viral hepatitis.

Conclusions

This study demonstrated comprehensively the gut microbiota characteristics in viral hepatitis, screened out crucial microbial functions related to viral hepatitis, and identified the potential microbial markers for predicting the risk of viral hepatitis.

1H, 13C, 15N backbone resonance assignment of apo and ADP-ribose bound forms of the macro domain of Hepatitis E virus through solution NMR spectroscopy

The genome of Hepatitis E virus (HEV) is 7.2 kilobases long and has three open reading frames. The largest one is ORF1, encoding a non-structural protein involved in the replication process, and whose processing is ill-defined. The ORF1 protein is a multi-modular protein which includes a macro domain (MD). MDs are evolutionarily conserved structures throughout all kingdoms of life. MDs participate in the recognition and removal of ADP-ribosylation, and specifically viral MDs have been identified as erasers of ADP-ribose moieties interpreting them as important players at escaping the early stages of host-immune response. A detailed structural analysis of the apo and bound to ADP-ribose state of the native HEV MD would provide the structural information to understand how HEV MD is implicated in virus-host interplay and how it interacts with its intracellular partner during viral replication. In the present study we present the high yield expression of the native macro domain of HEV and its analysis by solution NMR spectroscopy. The HEV MD is folded in solution and we present a nearly complete backbone and sidechains assignment for apo and bound states. In addition, a secondary structure prediction by TALOS + analysis was performed. The results indicated that HEV MD has a α/β/α topology very similar to that of most viral macro domains.

Seven years (2015-2021) of blood donor screening for HEV-RNA in France: lessons and perspectives

BACKGROUND

The French health authorities are considering expanding the current selective hepatitis E virus (HEV)-RNA testing procedure to include all donations in order to further reduce transfusion-transmitted HEV infection. Data obtained from blood donors (BDs) tested for HEV-RNA between 2015 and 2021 were used to assess the most efficient nucleic acid testing (NAT) strategy.

MATERIALS AND METHODS

Viral loads (VLs) and the plasma volume of blood components, as well as an HEV-RNA dose of 3.85 log IU as the infectious threshold and an assay with a 95% limit of detection (LOD) at 17 IU/mL, were used to assess the proportion of: (i) HEV-RNA-positive BDs that would remain undetected; and (ii) blood components associated with these undetected BDs with an HEV-RNA dose >3.85 log IU, considering 4 NAT options (Individual testing [ID], MP-6, MP-12, and MP-24).

RESULTS

Of the 510,118 BDs collected during the study period, 510 (0.10%) were HEV-RNA-positive. Based on measurable VLs available in 388 cases, 1%, 15.2%, 21.8%, and 32.6% of BDs would theoretically pass undetected due to a VL below the LOD of ID, MP-6, MP-12, and MP-24 testing, respectively. All BDs associated with a potentially infectious blood component would be detected with ID-NAT while 13% of them would be undetected with MP-6, 19.6% with MP-12, and 30.4% with MP-24 depending on the plasma volume. No red blood cell (RBC) components with an HEV-RNA dose >3.85 log IU would enter the blood supply, regardless of the NAT strategy used.

DISCUSSION

A highly sensitive ID-NAT would ensure maximum safety. However, an MP-based strategy can be considered given that: (i) the risk of transmission is closely related to the plasma volume of blood components; (ii) RBC are the most commonly transfused components and have a low plasma content; and (iii) HEV-RNA doses transmitting infection exceed 4 log IU. To minimise the potential risk associated with apheresis platelet components and fresh frozen plasma, less than 12 donations should be pooled using an NAT assay with a LOD of approximately 20 IU/mL.

The role of non-coding RNAs in the diagnosis of different stages (HCC, CHB, OBI) of hepatitis B infection

Despite the availability of an effective hepatitis B virus (HBV) vaccine and universal immunization schedules, HBV has remained a health problem in various stages such as occult hepatitis B infection (OBI), chronic hepatitis B (CHB), and hepatocellular carcinoma (HCC), which is considered one of the possible phases during chronic HBV infection. OBI is defined as the persistence of HBV genomes in hepatocytes of patients with a negative HBV surface antigen (HBsAg) test and detectable or undetectable HBV DNA in the blood. OBI is occasionally associated with infection caused by mutant viruses that produce a modified HBsAg that is undetected by diagnostic procedures or with replication-defective variations. Many aspects of HBV (OBI more than any other stage) including prevalence, pathobiology, and clinical implications has remained controversial. According to a growing body of research, non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been linked to the development and progression of a number of illnesses, including viral infectious disorders. Despite a shortage of knowledge regarding the expression and biological activities of lncRNAs and miRNAs in HBV infection, Hepatitis B remains a major global public health concern. This review summarizes the role of lncRNAs in the diagnosis and treatment of different stages of hepatitis B infection.

Expression Profiles of Hepatic Immune Response Genes in HEV Infection

Hepatitis E is a liver inflammation caused by infection with the hepatitis E virus (HEV). Every year, there are an estimated 20 million HEV infections worldwide, leading to an estimated 3.3 million symptomatic cases of hepatitis E. HEV viral load has been studied about the disease progression; however, hepatic the host gene expression against HEV infection remains unknown. Methods: We identified the expression profiles of hepatic immune response genes in HEV infections. Fresh blood samples were collected from all the study subjects (130 patients and 124 controls) in 3ml EDTA vacutainers. HEV viral load was determined by a real-time PCR. The total RNA was isolated from the blood using the TRIZOL method. The expression of theCCL2, CCL5, CXCL10, CXCL16, TNF, IFNGR1, and SAMSN1 genes was studied in the blood of 130 HEV patients and 124 controls using a real-time PCR. Results: Gene expression profiles indicate high levels of CCL2, CCL5, CXCL10, CXCL16, TNF, IFNGR1, and SAMSN1 genes that might lead to the recruitment of leukocytes and infected cell apoptosis. Conclusion: Our study demonstrated distinct differences in the expression profiles of host immune response-related genes of HEV infections and provided valuable insight into the potential impact of these genes on disease progression.

A Rare Case of Chronic Liver Disease in a Patient Who Previously Presented With Hepatitis E

Hepatitis E virus (HEV) is among the most common causes of acute viral hepatitis. It typically causes acute infection, but some cases of chronic infection have also been recorded. These cases were particularly seen in developed countries, in patients who were immunocompromised, organ transplant recipients, or those with underlying hematological malignancy. However, we encountered a case of hepatitis E presenting as a chronic liver disease in an immunocompetent patient from a developing country. Therefore, more underlying risk factors need to be studied, which may lead to such a rare presentation of hepatitis E.

Hepatitis E Virus (HEV) in Makkah, Saudi Arabia: A Population-Based Seroprevalence Study

BACKGROUND

The Hepatitis E virus (HEV) is a common cause of viral hepatitis worldwide. Little is known about the seroprevalence of HEV in the general population of Saudi Arabia.

METHODS

A community-based cross-sectional HEV seroprevalence study was conducted in Makkah, Saudi Arabia. Anti-HEV IgG antibodies were detected in sera using an in-house ELISA. The frequency of HEV sageerology and its correlation with demographic, and environmental factors were evaluated.

RESULTS

Enrollment consisted of 1329 individuals, ages ranged from 8 to 88 years, the mean age was 30.17 years, the median age was 28yrs, and the male: female ratio was 1.15. The overall seroprevalence was 23.8% (316/1329). Males had significantly higher seroprevalence than females (66.1 vs. 33.9%; p < 0.001). Seroprevalence had significant correlations with age, occupation, and lack of regular water supply and housing conditions.

CONCLUSIONS

This is the first HEV community-based seroprevalence study from Saudi Arabia. Results show that the HEV is endemic in Makkah and affects all age groups and occupations. HEV affects more males than females and those living in crowded accommodations without a regular supply of water. Further studies are required across all regions of Saudi Arabia to determine the country's seroprevalence of active or past infection using tests for HEV IgG, HEV IgM antibodies and/or HEV RNA and underlying determinants of transmission.