Hepatitis E virus infection: Epidemiology and treatment implications

Acalculous Cholecystitis in COVID-19 Patients: A Narrative Review

Acute acalculous cholecystitis (AAC) represents cholecystitis without gallstones, occurring in approximately 5-10% of all cases of acute cholecystitis in adults. Several risk factors have been recognized, while infectious diseases can be a cause of cholecystitis in otherwise healthy people. Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has spread worldwide, leading to an unprecedented pandemic. The virus enters cells through the binding of the spike protein to angiotensin-converting enzyme 2 (ACE2) receptors expressed in many human tissues, including the epithelial cells of the gastrointestinal (GI) tract, and this explains the symptoms emanating from the digestive system. Acute cholecystitis has been reported in patients with COVID-19. The purpose of this review is to provide a detailed analysis of the current literature on the pathogenesis, diagnosis, management, and outcomes of AAC in patients with COVID-19.

Acalculous Cholecystitis in COVID-19 Patients: A Narrative Review

Acute acalculous cholecystitis (AAC) represents cholecystitis without gallstones, occurring in approximately 5–10% of all cases of acute cholecystitis in adults. Several risk factors have been recognized, while infectious diseases can be a cause of cholecystitis in otherwise healthy people. Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has spread worldwide, leading to an unprecedented pandemic. The virus enters cells through the binding of the spike protein to angiotensin-converting enzyme 2 (ACE2) receptors expressed in many human tissues, including the epithelial cells of the gastrointestinal (GI) tract, and this explains the symptoms emanating from the digestive system. Acute cholecystitis has been reported in patients with COVID-19. The purpose of this review is to provide a detailed analysis of the current literature on the pathogenesis, diagnosis, management, and outcomes of AAC in patients with COVID-19.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially immunosuppressed individuals. Moreover, ribavirin therapy in the acute phase of infection provides major benefits for those at high risk of acute liver failure (ALF)/acute-on-chronic liver failure (ACLF). Pegylated interferon α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins, albumin, and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, ursodeoxycholic acid, Obeticholic acid, S-adenosylmethionine, etc. for removing jaundice. HEV infection during pregnancy and patients with underlying liver disease may develop liver failure. For these patients, active monitoring, standard care, and supportive treatment are the foundations. Ribavirin has successfully been used to prevent liver transplantation (LT). Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers, or until LT. LT is widely considered as irreplaceable and definitive treatment for liver failure, particularly for patients who do not improve with supportive measures to sustain life.

Research on a rat model of genotype IV swine hepatitis E virus

BACKGROUND

Hepatitis E virus (HEV) is an important zoonotic pathogen, Genotypes 3 and 4 are the main zoonotic genotype. Due to the lack of mature and effective culture cell lines, researches on genotype IV swine HEV (SHEV-4) infection and pathogenic mechanism have been carried out in pigs, gerbils and non-human primate models.

OBJECTIVES

The aim of this study was to establish a rat infection model by intra-peritoneal infection with SHEV-4, which provided a new research idea and scientific basis for further revealing the mechanism of HEV infection and preventing HEV infection.

METHODS

SHEV-4 virus was administered intra-peritoneally to 6- to 8-week-old mice to observe the serological changes and virus release.

RESULTS

According to the results of the rat serum HEV IgG, ALT and AST levels, swine HEV, minus-strand HEV RNA can infect Sprague-Dawley rats across species, and there are no obvious clinical symptoms after infection. HEV RNA was detected in most tissues and organs after infection, but the viral load was low. The liver had pathological changes of chronic hepatitis.

CONCLUSIONS

We found that the rat model of porcine HEV infection is a small animal model suitable for the study of HEV infection.

Seroprevalence and Potential Risk Factors of Hepatitis E Virus among Pregnant Women in Khartoum, Sudan

Although hepatitis E virus (HEV) infection has been widely understood as a public health concern in pregnant females, it is sometimes overlooked because of unusual observations of hepatitis E-induced complications during pregnancy. The objective of this descriptive cross-sectional study was to find out how frequent Hepatitis E virus infection is in pregnant women in Sudan. Blood samples were collected from pregnant women (n = 90) attending Khartoum North Hospital from February to December 2019. The specimens were investigated for Hepatitis E virus IgG and IgM antibodies using the commercial kits based on the enzyme immunosorbent assay (ELISA) technique. Out of ninety pregnant women, 36 (40%) were found positive for IgG antibodies, and 5 (6%) were tested positive for IgM antibodies. In addition, 13 (14.5%) of the positive cases are women in their third trimester. These data showed a significant association between previous Hepatitis E virus infection and miscarriage (p <0.001). This study did not find a significant association between maternal and gestation age, education, water sources, and hepatitis E virus infection. In conclusion, there was a high percentage of HEV infections among pregnant women attending Khartoum North Hospital. This study estimates the Hepatitis E virus burden in Khartoum state, but more extensive studies are required to confirm the burden in Sudan.

First Report of the HEV Seroprevalence and the Risk Factor Assessment in the West Bank, Palestine, during the Period of 2015-2017

Hepatitis E virus is emerging viral hepatitis with hyperendemicity in many countries. Data on the burden of disease is not available in Palestine. This study aims to determine the seroprevalence and the risk factors of the HEV among the general population of the West Bank, Palestine. In this cross-sectional study, a total of 432 sera samples from 40 localities in the eleven districts of the West Bank and Jerusalem, Palestine, during the period of March 2015 to March 2017, were tested for HEV-IgG. A structured questionnaire was used to collect data of the participants' demographics and disease risk factors. The overall seroprevalence was 3.7%. Level of education was significantly inversely associated with HEV seropositivity (P=0.04). Purely spatial analysis did not detect any significant cluster related to the distribution of HEV-IgG cases; however, living in the southern West Bank is shown to be significantly associated with HEV. Age was also associated with HEV seropositivity. The young (<19 years) and adults (>40 years) had the highest prevalence, compared to those between 20 to 39 years old (P=0.12). Furthermore, males and those in contact with animals were associated with HEV seropositivity (P=0.1 and 0.3, respectively). In conclusion, the seroprevalence of HEV IgG in the West Bank, Palestine is low. Several well-investigated risk factors cannot be supported by our results due to the small number of the positive HEV-IgG samples. Finally, this study is useful for providing a first look into the seroepidemiology of HEV in Palestine.

Advances in the Study of Acute Acalculous Cholecystitis: A Comprehensive Review

BACKGROUND

Acute acalculous cholecystitis (AAC) is characterized by acute necrotizing inflammation with no calculi and is diagnosed based on imaging, intraoperative, and pathological examinations.

KEY MESSAGE

Although AAC has been studied clinically for a long time, it remains difficult to diagnose and treat. The pathogenesis of AAC is still not fully understood, and it is often regarded as a relatively independent clinical disease that is different from acute calculous cholecystitis (ACC). Pathological studies suggest that AAC is the manifestation of a critical systemic disease, while ACC is a local disease of the gallbladder.

SUMMARY

Concerning the pathogenesis, diagnosis, and treatment of AAC, we reviewed the research progress of AAC, which will enhance the understanding of the early diagnosis and treatment of AAC.

Global burden of acute viral hepatitis and its association with socioeconomic development status, 1990-2019

BACKGROUND & AIMS

Acute viral hepatitis (AVH) represents an important global health problem; however, the progress in understanding AVH is limited because of the priority of combating persistent HBV and HCV infections. Therefore, an improved understanding of the burden of AVH is required to help design strategies for global intervention.

METHODS

Data on 4 major AVH types, including acute hepatitis A, B, C, and E, excluding D, were collected by the Global Burden of Disease (GBD) 2019 database. Age-standardized incidence rates and disability-adjusted life year (DALY) rates for AVH were extracted from GBD 2019 and stratified by sex, level of socio-demographic index (SDI), country, and territory. The association between the burden of AVH and socioeconomic development status, as represented by the SDI, was described.

RESULTS

In 2019, there was an age-standardized incidence rate of 3,615.9 (95% CI 3,360.5-3,888.3) and an age-standardized DALY rate of 58.0 (47.3-70.0) per 100,000 person-years for the 4 major types of AVH. Among the major AVH types, acute hepatitis A caused the heaviest burden. There was a significant downward trend in age-standardized DALY rates caused by major incidences of AVH between 1990 and 2019. In 2019, regions or countries located in West and East Africa exhibited the highest age-standardized incidence rates of the 4 major AVH types. These rates were stratified by SDI: high SDI and high-middle SDI locations recorded the lowest incidence and DALY rates of AVH, whereas the low-middle SDI and low SDI locations showed the highest burden of AVH.

CONCLUSIONS

The socioeconomic development status and burden of AVH are associated. Therefore, the GBD 2019 data should be used by policymakers to guide cost-effective interventions for AVH.

LAY SUMMARY

We identified a negative association between socioeconomic development status and the burden of acute viral hepatitis. The lowest burden of acute viral hepatitis was noted for rich countries, whereas the highest burden of acute viral hepatitis was noted for poor countries.

Hepatitis E Virus in the Food of Animal Origin: A Review

Hepatitis E virus (HEV) is a cosmopolitan foodborne pathogen. The viral agent infects humans through the consumption of contaminated food (uncooked or undercooked). Most cases of infection are asymptomatic and for this reason, this pathology is considered underdiagnosed. Domestic and wild animals are considered natural reservoirs: that is, domestic pig, wild boar, sheep, goat, deer, rabbit, and so on. Therefore, various work categories are at risk: that is, veterinarians, farmers, hunters, slaughterhouse workers, and so on. In these last decades, researchers found a high percentage of positivity to the molecular viral detection in several food matrices included: ready-to-eat products, processed meat products, milk, and shellfish. This review aims to provide an international scenario regarding HEV ribonucleic acid (RNA) detection in several foodstuffs. From this investigative perspective, the study aims to highlight various gaps of the current knowledge about technologies treatments' impact on viral loads. The purpose was also to provide an innovative point of view "One Health"-based, pointing out the strategic role of environmental safety.

Viral Hepatitis E and Chronicity: A Growing Public Health Concern

Hepatitis E viral infection recently emerges as a global health concern. Over the last decade, the understanding of hepatitis E virus (HEV) had changed with the discovery of new genotypes like genotype-7 and genotype-8 with associated host and mode of infection. Diversification in the mode of hepatitis E infection transmission through blood transfusion, and organ transplants in contrast to classical feco-oral and zoonotic mode is the recent medical concern. The wide spectrum of infection ranging from self-limiting to acute liver failure is now overpowered by HEV genotype-specific chronic infection especially in transplant patients. This concern is further escalated by the extra-hepatic manifestations of HEV targeting the central nervous system (CNS), kidney, heart, and pancreas. However, with the development of advanced efficient cell culture systems and animal models simulating the infection, much clarity toward understanding the pathogenetic mechanism of HEV has been developed. Also this facilitates the development of vaccines research or therapeutics. In this review, we highlight all the novel findings in every aspect of HEV with special emphasis on recently emerging chronic mode of infection with specific diagnosis and treatment regime with an optimistic hope to help virologists and/or liver specialists working in the field of viral hepatitis.

Serological Survey on Bacterial and Viral Pathogens in Wild Boars Hunted in Tuscany

Wild boar (Sus scrofa) is one of the large mammals most spread worldwide, including Italy. This animal is highly adaptable, and its population has rapidly increased in many areas in Europe. Central Italy, as well as Tuscany region, is an area particularly suitable for wild boar. In order to verify the role of this animal species in the epidemiology of some important infectious diseases for livestock and humans, a seroepidemiological survey on Brucella spp., Leptospira spp., Mycoplasma hyopneumoniae, Pseudorabies virus (PrV), and Hepatitis E virus (HEV) has been performed on 374 sera collected from wild boar during 2015/2016 and 2016/2017 hunting seasons. Overall, 2 out of 374 sera (0.53%) tested positive to Brucella spp., 33 out of 374 sera (8.82%) tested positive for Leptospira spp., while 79 out of 374 (21.12%) were positive for M. hyopneumoniae. Considering viral pathogens, serology indicated that 107 out of 374 (28.60%) samples scored positive for PrV, while 186 out of 374 (49.73%) for HEV. This investigation indicated that wild boar free ranging in the study area are potential hosts for different etiological agents. This animal could contribute to maintaining and/or disseminating some bacterial or viral pathogens to humans (especially hunters) and domestic animals, especially in free range farms.

Prevalence of hepatitis E virus in thalassemia patients with hepatitis C in Tehran, Iran

BACKGROUND AND OBJECTIVES

HEV infection is predominantly spread via the fecal-oral route; however, due to the presence of HEV RNA in the serum of healthy blood donors, there is a possibility of the transmissibility of HEV infection through blood. Multi-transfused thalassemia patients are one of the high risk groups for blood borne viruses. In this study, we evaluated the prevalence of HEV antibodies and HEV-RNA in thalassemia patients with HCV infection.

MATERIALS AND METHODS

120 anti-HCV positive thalassemia patient serum samples from Tehran province during April-June 2019 were assessed for the presence of total anti-HEV antibodies using of HEV Ab ELISA kit. All serum samples were assayed by Nested RT-PCR to detect HEV-RNA.

RESULTS

The results of ELISA test showed that 2 out of 120 (1.67%) samples were positive for anti-HEV Ab. There was no statistically significant difference between anti-HEV antibody prevalence rate and sex, age and other risk factors. None of 120 (0.00%) samples were positive for HEV-RNA by Nested RT-PCR.

CONCLUSION

Seroprevalence of HEV in our study group was 1.67% which is less than HEV seroprevalence rate in Iranian general population. Therefore, it can be conclude that transmission of HEV infection via blood transfusion seems to be uncommon in Iran and the fecal-oral route can be the predominant mode of transmission in Iran; however, more studies are required to confirm this issue.

Prevalence of hepatitis E virus infection among people and swine in mainland China: A systematic review and meta-analysis

Hepatitis E virus (HEV) infection remains an important public health problem, and it is endemic primarily in developing countries. This study aimed to evaluate the seroprevalence of HEV among the general population, occupational population and swine in mainland China and its risk factors based on a systematic review and meta-analysis. Systematic search from EMBASE, PubMed, Web of Science, Cochrane Library and several Chinese databases, such as Wanfang (WF) Data, China National Knowledge Infrastructure (CNKI), Chinese Science and Technology Periodical Database (VIP) and SINOMED, was searched from inception up to 25 April 2018. The overall seroprevalence of HEV and its corresponding 95% confidence interval (CI) as well as the correlation coefficients between different groups were estimated using stata 12.0 and r-3.4.1 software. Potential sources of heterogeneity were explored using subgroup and sensitivity analyses. Twenty-eight studies with 57,274 participants (including human and swine) were included. The seroprevalence of anti-HEV immunoglobulin G (IgG) among the general population, occupational population and swine was 27.3% (95% CI: 22.4-32.2), 47.4% (95% CI: 40.1-54.8) and 66.4% (95% CI: 61.7-71.1), respectively. The overall prevalence of IgM among the general population was 1.8% (95% CI: 0.7-2.9). The odds ratio for the occupational population, as compared to the general population, was 2.63. The highest anti-HEV IgG prevalence (59%) was observed in East China, whereas the lowest (34.8%) was noted in Northeast and North China. In the occupational population, the highest prevalence (77.0%) was observed among swine vendors. Seven studies included 30,392 participants (humans and swine); the correlation coefficient for the prevalence of anti-HEV IgG between the professional population and adult pigs was 0.88. Sensitivity analyses showed that the stability of results was not considered significant. This research found that HEV is common in China, and contact with pork or other pig products may be an important mode of HEV transmission.

The Serological Surveillance of Hepatitis E virus among Hunters and Foresters in Eastern Poland

The aim of the study was the analysis of the occurrence of specific antibodies against HEV among hunters and foresters who are at risk to be exposed. The study group consisted of 210 hunters (23-80 years old) and 60 foresters (22-64 years old). Anti-HEV IgG were present in 3.81% of the samples of the hunters and in 5% of the samples of the foresters. The statistical analysis shows no significant differences in the results anti-HEV IgG between the groups of hunters and foresters (p = 0.5278). Significantly higher anti-HEV IgG titers were found in the older age group (> 55 years old).

Development of new hepatitis E vaccines

Hepatitis E virus (HEV) infection is an emerging zoonotic disease posing a severe threat to public health in the world, especially to pregnant women. Currently, no specific treatments are available for HEV infection. Therefore, it is crucial to develop vaccine to prevent this infection. Although several potential candidate vaccines against HEV have been studied for their immunogenicity and efficacy, only Hecolin® which is developed by Xiamen Innovax Biotech Co., Ltd. and approved by China Food and Drug Administration (CFDA) in 2012, is the licensed HEV vaccine in the world so far. Extensive studies on safety, immunogenicity and efficacy in phase III clinical trials have shown that Hecolin® is a promising vaccine for HEV prevention and control. In this article, the advances on HEV vaccine development and research are briefly reviewed.

Hepatitis E Virus in Wild Boars and Spillover Infection in Red and Roe Deer, Germany, 2013-2015

To determine animal hepatitis E virus (HEV) reservoirs, we analyzed serologic and molecular markers of HEV infection among wild animals in Germany. We detected HEV genotype 3 strains in inner organs and muscle tissues of a high percentage of wild boars and a lower percentage of deer, indicating a risk for foodborne infection of humans.

Hepatitis E virus: advances and challenges

At least 20 million hepatitis E virus (HEV) infections occur annually, with >3 million symptomatic cases and ∼60,000 fatalities. Hepatitis E is generally self-limiting, with a case fatality rate of 0.5-3% in young adults. However, it can cause up to 30% mortality in pregnant women in the third trimester and can become chronic in immunocompromised individuals, such as those receiving organ transplants or chemotherapy and individuals with HIV infection. HEV is transmitted primarily via the faecal-oral route and was previously thought to be a public health concern only in developing countries. It is now also being frequently reported in industrialized countries, where it is transmitted zoonotically or through organ transplantation or blood transfusions. Although a vaccine for HEV has been developed, it is only licensed in China. Additionally, no effective, non-teratogenic and specific treatments against HEV infections are currently available. Although progress has been made in characterizing HEV biology, the scarcity of adequate experimental platforms has hampered further research. In this Review, we focus on providing an update on the HEV life cycle. We will further discuss existing cell culture and animal models and highlight platforms that have proven to be useful and/or are emerging for studying other hepatotropic (viral) pathogens.

Guillain-Barre syndrome caused by hepatitis E infection: case report and literature review

Background

Hepatitis E infection is a global disorder that causes substantial morbidity. Numerous neurologic illnesses, including Guillain–Barre syndrome (GBS), have occurred in patients with hepatitis E virus (HEV) infection.

Case presentation

We report a 58 year-old non-immunocompromised man who presented with progressive muscle weakness in all extremities during an episode of acute HEV infection, which was confirmed by measuring the anti-HEV IgM antibodies in the serum. Both cerebrospinal fluid examination and electrophysiological study were in agreement with the diagnosis of HEV-associated GBS. Following the treatment with intravenous immunoglobulin, the patient’s neurological condition improved rapidly.

Conclusions

HEV infection should be strongly considered in patients with neurological symptoms, especially those with elevated levels of liver enzymes.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-2959-2) contains supplementary material, which is available to authorized users.

Prevalence, risk factors and molecular evaluation of hepatitis E virus infection among pregnant women resident in the northern shores of Persian Gulf, Iran

BACKGROUND

Although Iran is reported to be an endemic country for hepatitis E virus (HEV), data on the prevalence of HEV infection among pregnant women are scarce and the epidemiology of HEV is unknown in most parts of the country. Therefore, this study was conducted to elucidate the prevalence, risk factors and genotypic pattern of HEV infection among pregnant women resident in the northern shores of Persian Gulf. This is the first report on the epidemiology of HEV infection among pregnant women in this territory.

METHODS

From October 2016 to May 2017, 1331 pregnant women participated in this study. The mean age ± SD of participants was 27.93±5.7 years with a range of 14-45 years. Serum samples of pregnant women were screened for the presence of anti-HEV total antibodies, anti-HEV IgG and anti-HEV IgM using commercially available ELISA kits (DIA.PRO, Milan, Italy). All anti-HEV IgG and anti-HEV IgM positive samples were tested for HEV RNA using two independent reverse transcriptase polymerase chain reaction (RT-PCR) assays, targeting ORF2 and ORF3 of HEV genome. In addition, 92 anti-HEV seronegative samples as well as 50 pooled seronegative samples were evaluated by two independent RT-PCR assays for validation of results.

RESULTS

Of the 1331 pregnant women, 84 women (6.3%, 95% CI: 5.1%-7.7%) were positive for anti-HEV antibodies, of which 83 women had anti-HEV IgG, and 11 women (0.83%, 95% CI: 0.47%-1.47%) had anti-HEV IgM. The highest rate of HEV seroprevalence was observed among Afghan immigrants (68.0%), uneducated pregnant women (46.51%) and those residents in Bushehr city (8.75%). All anti-HEV IgG and/or IgM positive samples were found to be negative for HEV RNA. In addition, all of the evaluated anti-HEV seronegative samples were negative for HEV RNA. HEV seropositivity among pregnant women was statistically associated with age, ethnicity, place of residence, number of pregnancies, and level of education. So that, low education levels, Afghan, residence in Bushehr city, age group >34 years, and more parities were risk factors for exposure to HEV. In contrast, HEV seropositivity was not associated with stage of gestation, history of abortion, and time of sampling.

CONCLUSION

The northern shores of Persian Gulf in Iran, with HEV seroprevalence of 6.3%, can be classified as an endemic geographical region for hepatitis E, and residents of Bushehr city, Afghan immigrants and uneducated women are the main at-risk populations in this territory.

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

Background

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

Methods

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

Results

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

Conclusions

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

High prevalence of hepatitis E virus infection in goats

Hepatitis E virus (HEV) is a major cause of acute hepatitis worldwide, primarily transmitted by fecal-oral route. Zoonotic transmission of HEV from HEV-infected pigs (pork) or cows (milk) to human or non-human primate has been confirmed, but the risk of HEV in goat is still rarely assessed. In the present study, stool, blood, tissues, and milk of goat were collected for HEV infection investigation from Dali City of Yunnan Province in China, where raw mutton and goat milk are traditionally consumed. Surprisingly, a high prevalence of HEV infection in goat was found. Phylogenetic analysis revealed that all HEV isolates from goat belong to genotype 4 and subtype 4h, and shared a high similarity homology (>99.6%) with HEV isolated from human, swine, and cows in the same area. Results suggested that goats are a previously unrecognized HEV host.

Seroprevalence and risk factors of hepatitis E virus infection among the Korean, Manchu, Mongol, and Han ethnic groups in Eastern and Northeastern China

Hepatitis E virus (HEV) infection is a serious public health concern in developing countries. China is regarded as an HEV-endemic area, but epidemiological data for HEV among different nationalities is limited. This study was conducted to estimate the seroprevalence and risk factors of HEV infection in Koreans (n = 520), Manchus (n = 303), Mongols (n = 217), and Hans (n = 802) in Eastern and Northeastern China between 2013 and 2015. A total of 366 (19.87%) out of 1842 samples were seropositive for IgG or IgM HEV-antibodies detected by enzyme-linked immunoassays. Among these groups, the Mongols had the highest seroprevalence of HEV infection (25.35%, 55/217), followed by the Koreans (23.65%, 123/520), the Manchus (19.80%, 60/303), and the Hans (15.96%, 128/802). Multiple analysis showed that the gender, consumption of raw/undercooked meat, source of drinking water, residence area, and age were significantly associated with HEV infection in four ethnic groups. The present results indicated that HEV infection was prevalent in Mongols, Koreans, Manchus, and Hans in the surveyed regions, which demonstrated the higher risk of transmitting HEV in multiple nationalities in Eastern and Northeastern China.

Pig model mimicking chronic hepatitis E virus infection in immunocompromised patients to assess immune correlates during chronicity

Chronic hepatitis E virus (HEV) infection is a significant clinical problem in immunocompromised individuals such as organ transplant recipients, although the mechanism remains unknown because of the lack of an animal model. We successfully developed a pig model of chronic HEV infection and examined immune correlates leading to chronicity. The conditions of immunocompromised patients were mimicked by treating pigs with an immunosuppressive regimen including cyclosporine, azathioprine, and prednisolone. Immunocompromised pigs infected with HEV progressed to chronicity, because 8/10 drug-treated HEV-infected pigs continued fecal virus shedding beyond the acute phase of infection, whereas the majority (7/10) of mock-treated HEV-infected pigs cleared fecal viral shedding at 8 wk postinfection. During chronic infection, serum levels of the liver enzyme γ-glutamyl transferase and fecal virus shedding were significantly higher in immunocompromised HEV-infected pigs. To identify potential immune correlates of chronic infection, we determined serum levels of cytokines and cell-mediated immune responses in pigs. Results showed that HEV infection of immunocompromised pigs reduced the serum levels of Th1 cytokines IL-2 and IL-12, and Th2 cytokines IL-4 and IL-10, particularly during the acute phase of infection. Furthermore IFN-γ-specific CD4⁺ T-cell responses were reduced in immunocompromised pigs during the acute phase of infection, but TNF-α-specific CD8⁺ T-cell responses increased during the chronic phase of infection. Thus, active suppression of cell-mediated immune responses under immunocompromised conditions may facilitate the establishment of chronic HEV infection. This pig model will aid in delineating the mechanisms of chronic HEV infection and in developing effective therapeutics against chronic hepatitis E.

Preliminary study on the detection of hepatitis E virus (HEV) antibodies in pigs and wild boars in Poland

Introduction: Although HEV infection in pigs does not pose a major economic risk to pork production, the risk of zoonotic transmission to humans is an important aspect of public health. HEV genotype 3 infections were reported in developed countries in individuals who had consumed raw meat or meat products from deer, wild boars, or pigs. The aim of the study was the analysis of the occurrence of HEV-specific antibodies among wild boars and domestic pigs in Poland. Material and Methods: A total of 290 samples from wild boars and 143 samples from pigs were tested. The antibodies were tested by ELISA. Results: The presence of anti-HEV IgG was demonstrated in 44.1% of pigs and 31.0% of wild boars. Anti-HEV IgG antibodies were detected in 1.4% of samples from pigs and in 2.1% of samples from wild boars at borderline level. The statistical analysis shows significant differences in the positive results for anti-HEV IgG between the groups of pigs and wild boars (P = 0.0263). Conclusion: Regular surveillance of the occurrence of HEV in swine and wild boars should be performed in the future.

Epidemiology of Hepatitis E in Pregnant Women and Children in Iran: A General Overview

From an epidemiological point of view, hepatitis E is an old infection in Iran, but only recently has its importance as a public health concern been considered from research and public health standpoints. As such, there is still a long road ahead to clarify the real burden of hepatitis E virus (HEV) infection in Iran. According to the available epidemiological studies, the seroprevalence of HEV infection among pregnant women is between 3.6% and 7.4%, and among Iranian children is between 0.9% to 8.5%, varying by geographic regions within the country and directly dependent upon the sanitary status of each. In addition to evaluating the sanitation level of a society, community-based seroprevalence studies of HEV infection demonstrate the most prevalent risk factors, the major routes of transmission, and the epidemiological patterns of HEV among that country's population. In this review, the current knowledge about the pathogenesis and epidemiology of HEV infection in pregnant women and children in Iran, as well as the recent advances in diagnosis, prevention and treatment of HEV infection have been summarized.

Role of Envelopment in the HEV Life Cycle

Hepatitis E virus (HEV), an enterically transmitted hepatotropic virus, was thought to be non-enveloped for decades. However, recent studies have revealed that the virus circulating in the patient’s blood is completely cloaked in host membranes and resistant to neutralizing antibodies. The discovery of this novel enveloped form of HEV has raised a series of questions about the fundamental biology of HEV and the way this virus, which has been understudied in the past, interacts with its host. Here, we review recent advances towards understanding this phenomenon and discuss its potential impact on various aspects of the HEV life cycle and immunity.

Guillain-Barré and Miller Fisher syndromes in patients with anti-hepatitis E virus antibody: a hospital-based survey in Japan

There have been reports from several countries that hepatitis E virus (HEV) infection is frequently associated with Guillain-Barré syndrome (GBS). This study aimed to determine the frequency of HEV infection associated with GBS in Japanese patients, and to clarify the clinical characteristics of these patients. Sera obtained from 63 patients with GBS or Miller Fisher syndrome (MFS) and 60 control subjects were examined for both HEV-IgM and HEV-IgG. Of the 63 patients, three were positive for both HEV-IgM and elevated hepatic enzymes: Two had GBS, and one had MFS. No control subjects were positive for HEV-IgM. Our study demonstrated that 4.8 % of patients with GBS or MFS from our institution had associated acute HEV infection. There were no clinical differences between GBS with HEV infection and other GBS cases. To our knowledge, this is the first survey in Japan of HEV-associated GBS or MFS.

Genotype 1 hepatitis E virus infection with acute acalculous cholecystitis as an extrahepatic symptom: a case report

Background

Hepatitis E virus (HEV) causes an acute viral hepatitis that is transmitted enterically. It is epidemic in Africa, Asia, the Middle East, and Central America. It is known that HEV can cause extrahepatic manifestations. Here, we report the first case of acalculous cholecystitis as an extrahepatic symptom of HEV.

Case presentation

A 24-year-old Japanese woman with no notable past medical history presented with complaints of fever and nausea while she was traveling in Australia; within the previous 2 months, she had also traveled to India and Africa. She visited a local hospital in Australia, and the laboratory tests showed significantly elevated levels of transaminase, so she was checked for viral hepatitis. After excluding hepatitis A, B, and C, as well as other causes of hepatitis, it was revealed that the patient was positive for HEV-IgM. Since she was a visitor to Australia, she was sent back to Japan and was transferred to our hospital. On day 4, the patient complained of right upper quadrant pain. Ultrasonography of the abdomen showed a thickened gallbladder wall without calculi. Acalculous cholecystitis was diagnosed from her course. No antibiotics were administered against it because there was no evidence of bacterial infection. The edematous wall showed significant improvement on day 11 and had returned to normal by day 14. The patient was discharged on day 16 because all of the symptoms had disappeared.

Conclusions

We found that HEV can cause acalculous cholecystitis as an extrahepatic manifestation. In addition, the cholecystitis could be resolved without any antibiotics.

Epidemiology of hepatitis E virus in Iran

Iran is known as an endemic country for hepatitis E virus (HEV) infection, while there are variations in the epidemiology of HEV infection throughout the country. The available epidemiological studies in different regions of Iran show HEV seroprevalence of 1.1%-14.2% among general population, 4.5% -14.3% among blood donors, 6.1%-22.8% among injecting drug users, 6.3%-28.3% among hemodialysis patients, 1.6%-11.3% among patients infected with other hepatitis viruses, 27.5% among patients with chronic liver disease, 30.8% among kidney transplant recipient patients, and 10%-16.4% among human immunodeficiency virus-infected patients. These variations reflect differences in the status of public health and hygiene, risk factors, and routes of transmission in different regions and groups. Therefore, it is necessary to review the epidemiology of HEV infection to determine the most prevalent risk factors and routes of transmission, and to evaluate the effectiveness of preventive strategies employed in the public health services of the country. Moreover, the other epidemiological aspects of HEV, including the genotypic pattern, extra hepatic manifestations, and incidence of chronic infection need to be investigated among Iranian population to expand the current knowledge on the epidemiology of HEV and to clarify the real burden of HEV infection. Therefore, this review was performed to provide a general overview regarding the epidemiology of HEV in Iran.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially in solid organ transplant patients. Pegylated interferon-α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins for adequate nutrition, albumin and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, and ursodeoxycholic acid and S-adenosylmethionine, and Traditional Chinese medicine for removing jaundice. Patients with underlying liver disease may develop liver failure. For these patients, supportive treatment is the foundation. Ribavirin has successfully been used to prevent liver transplantation. Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers or until liver transplantation. Liver transplantation is widely considered as irreplaceable and definitive treatment for acute-on-chronic liver failure, particularly for patients who do not improve with supportive measures to sustain life.