Spectrum of hepatitis E virus infection in India

Discovery of Hepatitis E and Its Impact on Global Health: A Journey of 44 Years about an Incredible Human-Interest Story

The story of the discovery of hepatitis E originated in the late 1970s with my extreme belief that there was a hidden saga in the relationship between jaundice and pregnancy in developing countries and the opportunity for a massive epidemic of viral hepatitis, which hit the Gulmarg Kashmir region in November 1978. Based on data collected from a door-to-door survey, the existence of a new disease, epidemic non-A, non-B hepatitis, caused by a hitherto unknown hepatitis virus, was announced. This news was received by the world community with hype and skepticism. In the early 1980s, the world watched in awe as an extreme example of human self-experimentation led to the identification of VLP. In 1990, a cDNA clone from the virus responsible for epidemic non-A, non-B hepatitis was isolated. Over the years, we traversed three eras of ambiguity, hope, and hype of hepatitis E research and conducted several seminal studies to understand the biology of HEV and manifestations of hepatitis E. Many milestones have been reached on the long and winding road of hepatitis E research to understand the structure, biology, and diversity of the agent, changing the behavior of the pathogen in developed countries, and the discovery of a highly effective vaccine.

A spectrum of viral diseases in Odisha state, eastern India: An evidence-based analysis from 2010-2017

Introduction

Emerging and re-emerging viral diseases are a major threat to public health. Odisha, being one of the coastal states in the country, reports many viral illnesses due to its typical geographical location. This study focuses on the prevalence of different viral diseases in the state of Odisha, India, from 2010-2017.

Material and Methods

A total of 43,397 patients with clinical suspicion of viral diseases were screened for different viral etiologies during 2010-2017. The laboratory diagnosis was conducted by serology (ELISA) and RT-PCR for 24 different viruses, i.e., dengue, chikungunya, Japanese encephalitis, hepatitis A virus, hepatitis E virus, hepatitis B virus, hepatitis C virus, rotavirus, herpes simplex virus-1 and herpes simplex virus-2, Epstein-Barr virus, cytomegalovirus, and respiratory viruses. Patients were enrolled from sporadic hospital admissions and outbreaks under different categories as per clinical diagnoses like fever with rash, diarrhoea, encephalitis, jaundice, respiratory illness, and fever of unknown etiology.

Results

The majority of patients belonged to exanthematous group, i.e., fever with rash (32.24%). The number of males was more in all categories except fever with rash, where females (53.34%) were more. Children <16 years of age were found to be the predominant age group for suspected viral diarrhoea (85.26%), encephalitis (76.96%), fever of unknown origin (40.16%), and respiratory infections (27.23%).

Conclusion

Not only vector-borne diseases pose a threat to the Odisha state, but other viral illnesses have also emerged. This detailed report of different viral diseases in the state of Odisha will support public health management.

Laboratory Diagnosis of HEV Infection

Serological and nucleic acid tests for detecting hepatitis E virus (HEV) have been developed for both epidemiologic and diagnostic purposes. The laboratory diagnosis of HEV infection depends on the detection of HEV antigen or HEV RNA in the blood, stool, and other body fluids, and serum antibodies against HEV (immunoglobulin [Ig]A, IgM, and IgG). Anti-HEV IgM antibodies and low avidity IgG can be detected during the acute phase of the illness and can last approximately 12 months, representing primary infection, whereas anti-HEV IgG antibodies can last more than several years, representing remote exposure. Thus, the diagnosis of acute infection is based on the presence of anti-HEV IgM, low avidity IgG, HEV antigen, and HEV RNA, while epidemiological investigations are mainly based on anti-HEV IgG. Although significant progress has been made in developing and optimizing different formats of HEV assays, improving their sensitivity and specificity, there are many shortcomings and challenges in inter-assay concordance, validation, and standardization. This article reviews the current knowledge on the diagnosis of HEV infection, including the most common available laboratory diagnostic techniques.

Hepatitis E virus infection in hematopoietic stem cell transplant recipients: a systematic review and meta-analysis

Although most patients with hepatitis E virus (HEV) infection are asymptomatic or have mild symptoms, its infection is generally underdiagnosed and overlooked. In immunocompromised patients, HEV infection can lead to acute liver failure and death. However, the clinical evidence of HEV infection in hematopoietic stem cell transplant (HSCT) recipients is scarce; thus, we conducted this systematic review and meta-analysis to assess the prevalence of HEV infection in this population. We searched MEDLINE, EMBASE, and the Cochrane Library databases from inception through October 2020 to identify studies that reported the prevalence of HEV infection among HSCT recipients. HEV infections were confirmed by HEV-IgG/IgM or HEV-RNA assay. A total of 1977 patients from nine studies with a follow-up time up to 40 months were included in the final analysis. The pooled prevalence of positive HEV-RNA was 3.0% (95% CI 2.3% to 4.0%). The pooled prevalence of positive HEV-IgG was 10.3% (95% CI 4.5% to 21.8%). The pooled prevalence of de novo HEV infection was 2.9% (95% CI 1.8% to 4.5%). Age and male gender were not associated with HEV-RNA or HEV-IgG positivity in the meta-regression analysis. In conclusion, the prevalence of HEV-IgG in HSCT recipients was about 10%, while the prevalence of HEV-RNA was only 3%. However, further studies that focus on the clinical outcomes in this population are warranted.

Hepatitis E and Pregnancy: An Unholy Alliance Unmasked from Kashmir, India

The adverse relationship between viral hepatitis and pregnancy in developing countries had been interpreted as a reflection of retrospectively biased hospital-based data collection by the West. However, the discovery of hepatitis E virus (HEV) as the etiological agent of an epidemic of non-A, non-B hepatitis in Kashmir, and the documenting of the increased incidence and severity of hepatitis E in pregnancy via a house-to-house survey, unmasked this unholy alliance. In the Hepeviridae family, HEV-genotype (gt)1 from genus Orthohepevirus A has a unique open reading frame (ORF)4-encoded protein which enhances viral polymerase activity and viral replication. The epidemics caused by HEV-gt1, but not any other Orthohepevirus A genotype, show an adverse relationship with pregnancy in humans. The pathogenesis of the association is complex and at present not well understood. Possibly multiple factors play a role in causing severe liver disease in the pregnant women including infection and damage to the maternal-fetal interface by HEV-gt1; vertical transmission of HEV to fetus causing severe fetal/neonatal hepatitis; and combined viral and hormone related immune dysfunction of diverse nature in the pregnant women, promoting viral replication. Management is multidisciplinary and needs a close watch for the development and management of acute liver failure. (ALF). Preliminary data suggest beneficial maternal outcomes by early termination of pregnancy in patients with lower grades of encephalopathy.

Setting a Course for Preventing Hepatitis E in Low and Lower-Middle-Income Countries: A Systematic Review of Burden and Risk Factors

BACKGROUND

Hepatitis E virus (HEV) is responsible for outbreaks of acute jaundice in Africa and Asia, many of which occur among displaced people or in crisis settings. Although an efficacious vaccine for HEV has been developed, we lack key epidemiologic data needed to understand how best to use the vaccine for hepatitis E control in endemic countries.

METHODS

We conducted a systematic review of articles published on hepatitis E in low-income and lower-middle-income countries in Africa and Asia. We searched PubMed, Scopus, and Embase databases to identify articles with data on anti-HEV immunoglobulin (Ig)G seroprevalence, outbreaks of HEV, or risk factors for HEV infection, disease, or death, and all relevant data were extracted. Using these data we describe the evidence around temporal and geographical distribution of HEV transmission and burden. We estimated pooled age-specific seroprevalence and assessed the consistency in risk factor estimates.

RESULTS

We extracted data from 148 studies. Studies assessing anti-HEV IgG antibodies used 18 different commercial assays. Most cases of hepatitis E during outbreaks were not confirmed. Risk factor data suggested an increased likelihood of current or recent HEV infection and disease associated with fecal-oral transmission of HEV, as well as exposures to blood and animals.

CONCLUSIONS

Heterogeneity in diagnostic assays used and exposure and outcome assessment methods hinder public health efforts to quantify burden of disease and evaluate interventions over time and space. Prevention tools such as vaccines are available, but they require a unified global strategy for hepatitis E control to justify widespread use.

Currently circulating genotypes of hepatitis E virus in India, 2014-2018

Purpose

Hepatitis E virus (HEV) is an emerging pathogen causing acute viral hepatitis worldwide. Clinical manifestations often occur in young adults with an increased mortality rate among pregnant women. HEV genotypes 1 and 4 are mainly reported among humans and swines, respectively.

Aims

The aim was to study the currently circulating genotypes of HEV in India.

Materials and Methods

A retrospective cross-sectional study was carried out at Manipal Institute of Virology to know the circulating genotypes of hepatitis E, spanning over 5 years from August 2014 to September 2018. The serum samples screened serologically positive and confirmed positive for active infection by real-time reverse transcriptase-polymerase chain reaction (PCR) (Real Star® HEV RT-PCR Kit 2.0, Altona Diagnostics, GmbH, Hamburg, Germany) were further subjected to nested conventional PCR targeting the RdRp gene of non-structural ORF1 region. The purified PCR product was sequenced in BigDye Terminator v3.1 Cycle Sequencing Kit (Life Technologies, Thermo Fisher Scientific, USA). The chromatograms obtained by sequencing were analysed using Sequencher 5.4.6, and HEV FASTA sequences were compared with reference sequences for HEV in GenBank Nucleotide Blast.

Results

During the study period, there were 317 cases of laboratory-confirmed cases of acute viral hepatitis comprising 202, 70, 43 and 2 cases of hepatitis A, E, B and C, respectively. Serum samples of 70 acute hepatitis cases were positive for anti-hepatitis E IgM. According to the clinical case classification, there were 66 cases of acute viral hepatitis and four cases of fulminant hepatic liver failure. The mean age of the patients was 30.3 years (standard deviation = 12.5). The samples from various parts of India were genotyped as 1a.

Conclusion

The HEV genotypes 1a was observed to be the currently circulating strain in the regions studied.

An update of the incidence of fulminant hepatitis due to viral agents during pregnancy

Fulminant hepatitis in pregnant women is one of the major public health issues and remains a challenging clinical problem with extremely high maternal and fetal morbidity and mortality, which, in parallel, viral factors are the most common cause of hepatic disorders and dysfunction during pregnancy that may lead to fulminant hepatic with a fast progression. Therefore, this review helps to inform clinicians about the current status of the incidence of fulminant hepatitis due to viral agents during pregnancy.

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.

Transmission of Hepatitis E Virus in Developing Countries

Hepatitis E virus (HEV), an RNA virus of the Hepeviridae family, has marked heterogeneity. While all five HEV genotypes can cause human infections, genotypes HEV-1 and -2 infect humans alone, genotypes HEV-3 and -4 primarily infect pigs, boars and deer, and genotype HEV-7 primarily infects dromedaries. The global distribution of HEV has distinct epidemiological patterns based on ecology and socioeconomic factors. In resource-poor countries, disease presents as large-scale waterborne epidemics, and few epidemics have spread through person-to-person contact; however, endemic diseases within these countries can potentially spread through person-to-person contact or fecally contaminated water and foods. Vertical transmission of HEV from infected mother to fetus causes high fetal and perinatal mortality. Other means of transmission, such as zoonotic transmission, can fluctuate depending upon the region and strain of the virus. For instance, zoonotic transmission can sometimes play an insignificant role in human infections, such as in India, where human and pig HEV infections are unrelated. However, recently China and Southeast Asia have experienced a zoonotic spread of HEV-4 from pigs to humans and this has become the dominant mode of transmission of hepatitis E in eastern China. Zoonotic HEV infections in humans occur by eating undercooked pig flesh, raw liver, and sausages; through vocational contact; or via pig slurry, which leads to environmental contamination of agricultural products and seafood. Lastly, blood transfusion-associated HEV infections occur in many countries and screening of donors for HEV RNA is currently under serious consideration. To summarize, HEV genotypes 1 and 2 cause epidemic and endemic diseases in resource poor countries, primarily spreading through contaminated drinking water. HEV genotypes 3 and 4 on the other hand, cause autochthonous infections in developed, and many developing countries, by means of a unique zoonotic food-borne transmission.

Viral hepatitis: Indian scenario

Viral hepatitis is a cause for major health care burden in India and is now equated as a threat comparable to the "big three" communicable diseases - HIV/AIDS, malaria and tuberculosis. Hepatitis A virus and Hepatitis E virus are predominantly enterically transmitted pathogens and are responsible to cause both sporadic infections and epidemics of acute viral hepatitis. Hepatitis B virus and Hepatitis C virus are predominantly spread via parenteral route and are notorious to cause chronic hepatitis which can lead to grave complications including cirrhosis of liver and hepatocellular carcinoma. Around 400 million people all over the world suffer from chronic hepatitis and the Asia-Pacific region constitutes the epicentre of this epidemic. The present article would aim to cover the basic virologic aspects of these viruses and highlight the present scenario of viral hepatitis in India.

Changing etiologies and outcome of liver failure in Southwest China

Background

The prognosis of liver failure depends greatly on the underlying cause, and there were few data about the prognosis, etiologies or trigger factors of liver failure in China based on long-term and large samples cohorts.

Methods

We screened out 3171 liver failure cases from 25467 patients hospitalized in our department between 2000 and 2012 according to Chinese criteria, and determined their etiologies and prognosis.

Results

97.3 % cases were associated with at least one of 25 identified factors. The 3 leading etiologies were HBV (91.6 %), alcohol (18.1 %) and antiviral therapy (AVT) related hepatitis B flares (6.7 %). Acute-on-chronic liver failure (ACLF) accounted for 92.1 % of all cases. 96.5 % ACLF cases were associated with HBV, in which the percentage of AVT related flares increased from 0 % in 2000 up to 11.5 % in 2012, and hepatitis virus superinfection declined from peak 19.3 % in 2002 down to 2.5 % in 2012. Three-month spontaneous survival (SS) rate of 3171 cases was 31.4 %, but improved from 17.4 % in 2000 up to 40.4 % in 2012. SS was significantly different among various etiological groups (P = 0.000). In HBV related liver failure aged 25 to 54 years, males accounted for 87.6 %, and had a progressively decreased SS with increasing age. From 25 to 54 years, SS was lower in male than in female HBV related liver failure, and having significant difference in cases of ages 40 to 44 years (27.6 % versus 50.9 %, P = 0.001).

Conclusion

Etiologies of liver failure were numerous and varied in southwest China. HBV was the most leading cause of liver failure, especially in ACLF. AVT related flares had become the third leading cause of ACLF. The prognosis of liver failure remained poor, but had markedly improved in recently 3 years. Middle-aged male HBsAg carriers had an extremely higher risk for liver failure and worse prognosis compared to female.

Etiologies of liver failure were numerous and varied in southwest China. HBV infection is the main cause of liver failure in southwest China, especially the major cause of ACLF. Antiviral related liver failure, especially the NUCs withdrawal induced ACLF were extremely increased, which has replaced the superinfection as the third important cause of HBV-ACLF.

The prognosis of liver failure is still poor, but the spontaneous survival rate showed a trend of steady rise in recent years. The prognosis of patients with liver failure caused by different causes also exists certain difference, the more damage factors bulls the worse prognosis.

The prognosis of the HBV and HCV reactivation induced by the steroids was poor.Interferon treatment of CHB in ACLF although rare, but should be taken into consideration seriously.

Patients with liver failure caused by different etiologies showed larger differences of gender and age distribution. Gender and age are the important factors with the occurrence and prognosis of HBV-ACLF.

Materno-Fetal Outcomes with Viral Hepatitis in Pregnancy

OBJECTIVE

To evaluate materno-fetal outcomes in pregnant women with jaundice.

METHODS

A prospective study was conducted over a period of 6 months in a tertiary care hospital of Delhi, India. 82 pregnant women with jaundice were included. The serum was screened for viral markers, liver function tests, and coagulation status.

RESULTS

The mean age of women was 27.3 ± 4.3 years. 43.9 % (n = 36) women were HEV positive, 36 % (n = 27) HBsAg positive, 4 % (n = 3) HAV positive and 1.3 % (n = 1) HCV positive. Intrahepatic cholestasis was diagnosed in 10.8 % (n = 8) of women. Maternal morbidity was evaluated in terms of chorioamnionitis (5.4 %, n = 3), encephalopathy (26.8 %, n = 15), and coagulopathy (67.9 %, n = 38). There were five maternal deaths, and all were unbooked with HEV-positive status and a bilirubin >15 mg/dl with deranged coagulogram and encephalopathy and IUDs. 79 women delivered vaginally, and three had cesarean section. Of the vaginal deliveries, 59.8 % (n = 49) went into spontaneous labor, and 25.5 % (n = 21) were induced for varied reasons (BPS < 6/10 (38 %, n = 8)) and progressive derangement of LFT (38 %, n = 8). Among the 71 deliveries, 29 (40.8 %) were IUD and 42 (59.1 %) were live born. On analyzing the morbidity data, it was found that HEV-positive women (deranged coagulogram 71.05 %, IUD 75.86 %, encephalopathy 80 %) had a poorer outcome as compared to their HBsAg positive counterparts (deranged coagulogram 10.52 %, IUD 13.79 %, encephalopathy 6.66 %).

CONCLUSION

Urgent redressal of issues pertaining to sanitation and provision for clean drinking water for citizens of India is the need of the hour as HEV is fecooral in transmission.

Hepatitis E virus: Current epidemiology and vaccine

Hepatitis E virus infections have been continuously reported in Indian subcontinent, Africa, southeast and central Asia, posing great health threats to the public, especially to pregnant women. Hecolin® is the only licensed HEV vaccine developed by Xiamen Innovax Biotech Co., Ltd. Extensive characterizations on antigenicity, physicochemical properties, efficacy in clinical trials, and manufacturing capability have made Hecolin® a promising vaccine for HEV control. However, there are many obstacles in large scale application of Hecolin®. Efforts are needed to further evaluate safety and efficacy in HEV risk populations, and to complement HEV standards for quality control. Passing World Health Organization prequalification and licensing outside China are priorities as these are also hindering Hecolin® promotion. Multilateral cooperation among Chinese vaccine manufacturers, Chinese National Regulatory Authorization (NRA) and WHO will expedite the entrance of Hecolin® into international market, so that Hecolin® could play its due role in global hepatitis E control.

Hepatitis E: an emerging global disease - from discovery towards control and cure

Hepatitis E is a systemic disease affecting the liver predominantly and caused by infection with the hepatitis E virus (HEV). HEV has marked genetic heterogeneity and is known to infect several animal species including pigs, boar, deer, mongoose, rabbit, camel, chicken, rats, ferret, bats and cutthroat trout. HEV is the sole member of the family Hepeviridae and has been divided into 2 genera: Orthohepevirus (mammalian and avian HEV) and Piscihepevirus (trout HEV). Human HEVs included within the genus Orthohepevirus are designated Orthohepevirus A (isolates from human, pig, wild boar, deer, mongoose, rabbit and camel). Hepatitis E is an important public health concern, and an estimated one-third of the world population has been infected with HEV. In recent years, autochthonous hepatitis E is recognized as a clinical problem in industrialized countries. Several animal species especially domestic swine, wild boar and wild deer are reservoirs of genotype HEV-3 and HEV-4 in these countries. Human infections occur through intake of uncooked or undercooked meat of the infected animals and pig livers or sausages made from these livers and sold in supermarkets. HEV can be transmitted through blood and blood component transfusions, and donor screening for HEV is under serious consideration. Chronic hepatitis E resulting in rapidly progressive liver cirrhosis and end-stage liver disease has been described in organ transplant patients. Ribavirin monotherapy attains sustained virological response in most patients. HEV 239 vaccine has been marketed in China and its long-term efficacy over four and a half years reported.

Laboratory Diagnosis of HEV Infection

Serological and nucleic acid tests for detecting hepatitis E virus (HEV) have been developed for both epidemiologic and diagnostic purposes. The laboratory diagnosis of HEV infection depends on the detection of HEV antigen, HEV RNA, and serum antibodies against HEV (immunoglobulin [Ig]A, IgM, and IgG). Anti-HEV IgM antibodies can be detected during the acute phase of the illness and can last approximately 4 or 5 months, representing recent exposure, whereas anti-HEV IgG antibodies can last more than 10 years, representing remote exposure. Thus, the diagnosis of acute infection is based on the presence of anti-HEV IgM, HEV antigen, and HEV RNA, while epidemiological investigations are mainly based on anti-HEV IgG. Although significant progress has been made in developing and optimizing different formats of HEV assays, improving their sensitivity and specificity, there are many shortcomings and challenges in inter-assay concordance, validation, and standardization. This article reviews the current knowledge on the diagnosis of HEV infection, including the most common available laboratory diagnostic techniques.

Hepatitis E virus infections in children age 0-15, Uganda outbreak, 2007

BACKGROUND

The epidemiology of hepatitis E virus (HEV) infections among children is not well understood, with some studies reporting that hepatitis E infections do not affect children.

OBJECTIVES

We analyzed seroepidemiologic data collected during a hepatitis E outbreak in Uganda to determine prevalence of past and recent HEV infections among children aged 0-15 years.

STUDY DESIGN

Individuals were randomly selected from a household census to participate in a seroprevalence survey. We analyzed data on IgM and IgG antibody to HEV among children aged 0-15 years. We categorized the study population by age group [aged 0-5, 6-10, and 11-15 years], and further stratified the youngest children [aged 0-1, 2-3, and 4-5 years]. Presence of IgG anti-HEV alone indicated past HEV infection, whereas recent infection was defined as presence of IgM anti-HEV with or without IgG anti-HEV.

RESULTS

Among children aged 0-15 years (N=244), prevalence of past HEV infection was 25.4% (62/244) and was highest among children aged 0-5 years [31.0% (27/87)]. Evidence of recent HEV infection was detected in 37.3% (91/244) of children aged 0-15 years. Among younger children, recent HEV infection increased with age from 4.3% (1/23) in children aged 0-1 year to 36.7% (11/30) in children aged 4-5 years.

CONCLUSION

These data show that children are not spared from HEV infections. Illness during childhood in developing countries is common and HEV infections may be misdiagnosed as another acute illness, or under diagnosed. The lack of clinical care, HEV diagnostics, and surveillance in developing countries limit our full understanding of hepatitis E epidemiology.

A study of viral hepatitis e infection in a tertiary care hospital in mysore, South India

Background.

 In this study, we aimed to explore the clinical and epidemiological profile of all patients with hepatitis E virus (HEV) who were admitted to a tertiary care hospital in Mysore, India and to further assess various factors that influence the prognosis of these patients.

Methods.

 Two hundred ninety patients with HEV infection were included in the study and interviewed. They were subjected to clinical examination and laboratory investigations, including complete hemogram, renal, and liver function tests. Viral markers for HBV, HAV, HCV, and HEV by hepatitis B surface antigen, anti-HAV, anti-HCV, and anti-HEV antibodies, respectively, were done using the enzyme-linked immunosorbent assay method. Final outcome was recorded in the form of discharge or death.

Results.

 Males had higher (82.8%) incidence of HEV infection. Yellowish discoloration of urine was the most common symptom, and icterus was the most common sign at presentation. Hepatomegaly was most common finding on abdominal examination. Mean duration of hospital stay was higher among diabetics (10 days vs 7.11 ± 3.52 days). Overall, mortality observed was 3.45%. A higher mean age (P = .000) and duration of hospital stay (P = .000) were associated with higher mortality. Mortality was significantly higher among patients with alcohol abuse (25% vs 0%) (P = .004). Higher mean prothrombin time-international normalised ratio (PT-INR) (1.6 ± 0.13 vs 1.21 ± 0.32), total bilirubin (20.3 ± 5.08 vs 11.33 ± 7.26 mg/dL), and direct bilirubin (15.05 ± 3.64 vs 6.35 ± 3.71 mg/dL) were associated with higher mortality, whereas lower mean serum albumin (2.6 ± 0.11 vs 3.41 ± 0.40 gm/dL) was associated with higher mortality. Increase in renal parameters (ie, urea [97 ± 33.48 vs 32.43 ± 18.41 mg/dL] and creatinine [2.9 ± 1.38 vs 1.12 ± 0.64 mg/dL]) and electrolyte imbalances (ie, hyperkalemia [5.95 ± 1.21 vs 4.29 ± 0.51 mmol/L] and hyponatremia [123 ± 3.56 vs 136.04 ± 2.97 mmol/L]) were associated with higher mortality. There were 20-fold increases in mean serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) values (SGPT: SGOT = 1.148) and a 1-fold increase in mean alkaline phosphatase.

Conclusions.

 Higher mean age, duration of hospital stay, PT-INR, total bilirubin, direct bilirubin, blood urea, serum creatinine, potassium values, alcohol abuse, presence of ascites, and fulminant hepatitis were associated with higher mortality, whereas lower mean serum albumin and sodium values were associated with higher mortality. Diabetics had a higher mean duration of hospital stay.

Protective immunity against HEV

Rural community of Dongtai City in eastern China is endemic for hepatitis E virus (HEV), with the zoonotic genotype 4 virus predominating. The virus appears to be widely distributed in environment at generally low levels, such that infection is common, but >97% of which are asymptomatic and provoke a modest antibody response. Naturally acquired immunity affords 75% protection against infection, prevents disease caused by primary infection and alleviates severity of the disease caused by the residual infection that had evaded host immune surveillance. The protection, however, is extended to a minority, while leaving the majority of population essentially without the benefits of immune protection. Vaccination affords similar level of protection as does natural immunity, but expands the protective coverage to the entire population.

Water borne hepatitis a and hepatitis e in malwa region of punjab, India

INTRODUCTION

Hepatitis-A virus infection (HAV) and Hepatitis E virus infection (HEV) are faecally contaminated water borne infection of great public interest in developing countries. HAV has a world-wide /dablestribution and affects infant and young children in developing countries and its epidemics are not very common. HEV is restricted to tropical countries and affects older children and young adults and its epidemics are common. Studies suggested that HEV is etiologically responsible for 10%-95% of admitted cases of hepatitis. Exposure rates over a period of time are different in different parts of the country and in different socio-economic groups. Aim of the study 1. To study the prevalence of HAV and HEV in the outbreak of hepatitis in certain areas of Malwa region of Punjab, India. 2. To determine the age specific prevalence rates of HAV and HEV. 3. To determine any change in the epidemiology of these infections.

MATERIAL AND METHODS

This study was conducted in the Department of Microbiology in GGMC and Hospital Faridkot, A leading Tertiary care hospital and the major referral centre of malwa region of Punjab,India. Collection and Serological Tests: 1.Venous blood samples of patients of acute hepatitis were taken. 2.Relavent information regarding their Age, Sex Education, Socio-economic status, personal and community hygiene were recorded. All of the sera were screened for IgM Antibody to HEV and HAV using IgM capture ELISA Kit (ASIA-LION Biotechnology for HEV and GENERAL BIOLOGICAL CORPORATION for HAV ) in accordance with the manufacturer's instructions. Result and Conclusion : 1.The outbreak was due to hepatitis A &E virus(HEV predominating resulting from fecal contamination of drinking water). 2.Hepatitis E is more widely prevalent 3.There is a change in the epidemiology of HAV so,more cases are seen in age group of more than 20 years.

Hepatitis e and acute liver failure in pregnancy

Hepatitis E virus is a positive strand RNA virus with three open reading frames which is transmitted predominantly through the fecal contamination of water and food. It is the most common cause of acute liver failure in endemic areas. Pregnant women especially from the Indian subcontinent and Africa are at increased risk of contracting acute HEV infection as well as developing severe complications including ALF. Transmission of HEV occurs from mother to unborn child. Both maternal and fetal complications may occur, including abortion, fetal demise, preterm labor and maternal or neonatal death. The precise reasons for increased susceptibility to HEV infection during pregnancy and associated severe disease are still an enigma. Management is supportive and termination of pregnancy is not recommended as a general rule. Prevention of infection is of vital importance, as availability of clean drinking water can reduce the burden of this disease in the community. There is a need for future research to focus on prevention of ALF in pregnancy and to study the disease pathogenesis, which is not explicitly understood at present. The availability of a vaccine may alter the natural course of the disease in this select population which is at risk.

Population Movement and Virus Spreading: HEV Spreading in a Pilgrimage City, Mashhad in Northeast Iran; an Example

BACKGROUND

Hepatitis E Virus (HEV) infection is a significant public health concern and responsible for large outbreaks of acute hepatitis in poor sanitary and living conditions.

OBJECTIVES

To investigate the impact of population movements on virus spreading, a large-scale population-based survey was performed in a pilgrimage- tourism area, the great Mashhad, capital city of Khorasan province.

PATIENTS AND METHODS

A cross-sectional study was carried out among 1582 randomly selected individuals from general population of Mashhad, north east of Iran, between May to September 2009. Serum samples were tested for total anti-HEV antibody using a specific enzyme linked immunoassay (ELISA) kit.

RESULTS

The prevalence of HEV infection was 14.2% (225/1582) with a maximum of 25.5 % (14/55) in densely populated areas. The highest prevalence was observed in visitant areas (≥ 20%) near the holly shrine with crowded hotels and inns. The differences between these areas and other districts were statistically significant (P < 0.001). The findings indicated that 13.2% (95/718) of males and 15.0% (130/864) of females were HEV positive; this difference is not significant. Seroprevalence increases with age rising , from 12.8% in subjects less than five years to 28.6% in individuals with more than 65 years old. Although, there were no meaningful differences between HEV seropositivity and socio-economic status, Illiterate individuals were significantly at higher risk for infection than educated persons (P < 0.001).

CONCLUSIONS

These findings demonstrated that, high prevalence of HEV is related to populated district, which can reach to the highest rate in hotels and inns close to visitants. Traditional sanitation and water supplying systems are the second important factor for the virus transmission. Therefore, it can be concluded that such areas need efficient surveillance systems to prevent the spreading of infectious diseases.

Hepatitis e: molecular virology and pathogenesis

Hepatitis E virus is a single, positive-sense, capped and poly A tailed RNA virus classified under the family Hepeviridae. Enteric transmission, acute self-limiting hepatitis, frequent epidemic and sporadic occurrence, high mortality in affected pregnants are hallmarks of hepatitis E infection. Lack of an efficient culture system and resulting reductionist approaches for the study of replication and pathogenesis of HEV made it to be a less understood agent. Early studies on animal models, sub-genomic expression of open reading frames (ORF) and infectious cDNA clones have helped in elucidating the genome organization, important stages in HEV replication and pathogenesis. The genome contains three ORF's and three untranslated regions (UTR). The 5' distal ORF, ORF1 is translated by host ribosomes in a cap dependent manner to form the non-structural polyprotein including the viral replicase. HEV replicates via a negative-sense RNA intermediate which helps in the formation of the positive-sense genomic RNA and a single bi-cistronic sub-genomic RNA. The 3' distal ORF's including the major structural protein pORF2 and the multifunctional host interacting protein pORF3 are translated from the sub-genomic RNA. Pathogenesis in HEV infections is not well articulated, and remains a concern due to the many aspects like host dependent and genotype specific variations. Animal HEV, zoonosis, chronicity in immunosuppressed patients, and rapid decompensation in affected chronic liver diseased patients warrants detailed investigation of the underlying pathogenesis. Recent advances about structure, entry, egress and functional characterization of ORF1 domains has furthered our understanding about HEV. This article is an effort to review our present understanding about molecular biology and pathogenesis of HEV.

Hepatitis E: Epidemiology and prevention

Hepatitis E is caused by the hepatitis E virus (HEV), the major etiologic agent of enterically transmitted non-A hepatitis worldwide. HEV is responsible for major outbreaks of acute hepatitis in developing countries, especially in many parts of Africa and Asia. The HEV is a spherical, non-enveloped, single-stranded, positive sense RNA virus that is approximately 32 nm to 34 nm in diameter and is the only member in the family Hepeviridae and genus Hepevirus. There are four distinct genotypes of HEV (genotypes 1-4). While genotype 1 is predominantly associated with large epidemics in developing countries, genotype 3 has recently emerged as a significant pathogen in developed countries. The clinical manifestations and the laboratory abnormalities of hepatitis E are not distinguishable from that caused by other hepatitis viruses. However, high mortality among pregnant women particularly during the third trimester distinguishes HEV from other causes of acute viral hepatitis. Specific etiologic diagnosis among infected cases can be made by serological testing or detection of viral nucleic acid by reverse transcription polymerase chain reaction. Although there are vaccine candidates that had been shown to be safe and efficacious in clinical trials, none are approved currently for use. There is no specific therapy for acute hepatitis E as treatment remains supportive.

Discovery of hepatitis E: the epidemic non-A, non-B hepatitis 30 years down the memory lane

Hepatitis E was first recognised during an epidemic of hepatitis, which occurred in Kashmir Valley in 1978. The epidemic involved an estimated 52,000 cases of icteric hepatitis with 1700 deaths. The disease had unique clinical and epidemiological features. The epidemic was water-borne with highly compressed epidemic curve. Following the epidemic, secondary waves of hepatitis did not occur. Clinical profile was characterized by cholestasis in around 20% of patients. The disease predominantly occurred in young adults. There was increased incidence and severity of the disease in pregnant women. A subset of patients had distinctive liver histology with bile plugs in the canaliculi and formation of pseudo-ductules by hepatocytes around the bile plugs. All surviving patients had self limiting disease. Sera lacked serological markers of acute hepatitis A and hepatitis B. Based on these data, the possibility of another human hepatitis virus distinct from post-transfusion non-A, non-B hepatitis was postulated. Balayan et al. (1983) successfully transmitted the disease into himself by oral administration of pooled stool extracts of 9 patients from a non-A, non-B hepatitis outbreak which had occurred in a Soviet military camp located in Afghanistan. Reyes et al. (1990) cloned and sequenced hepatitis E virus genome. Over the years, hepatitis E was identified as a major health problem in developing countries with unsafe water supplies and poor sanitary disposal. Data from sero-surveys forced re-evaluation of the epidemiology of hepatitis E and gave an indirect indication to vocationally acquired HEV infections in industrialized countries. Soon, autochthonous hepatitis E was recognised as a clinical problem in such countries. Several animal species especially domestic swine, wild boar and wild deer were found to be reservoirs of hepatitis E virus genotype 3 & 4 in these countries. Human infections occur through intake of uncooked or undercooked meat of the infected animals and pig livers or sausages made from these livers and sold in supermarkets. Chronic hepatitis E resulting in rapidly progressive liver cirrhosis and end stage liver disease was described in organ transplant patients and those with other immunodeficiency states from many European countries. Two recombinant hepatitis E virus vaccines have successfully undergone phase 3 trials.

Serological diagnostics of hepatitis E virus infection

Development of accurate diagnostic assays for the detection of serological markers of hepatitis E virus (HEV) infection remains challenging. In the course of nearly 20 years after the discovery of HEV, significant progress has been made in characterizing the antigenic structure of HEV proteins, engineering highly immunoreactive diagnostic antigens, and devising efficient serological assays. However, many outstanding issues related to sensitivity and specificity of these assays in clinical and epidemiological settings remain to be resolved. Complexity of antigenic composition, viral genetic heterogeneity and varying epidemiological patterns of hepatitis E in different parts of the world present challenges to the refinement of HEV serological diagnostic assays. Development of antigens specially designed for the identification of serological markers specific to acute infection and of IgG anti-HEV specific to the convalescent phase of infection would greatly facilitate accurate identification of active, recent and past HEV infections.

Clinical characteristics of hepatitis E in a "Non-Endemic" population

Hepatitis E virus (HEV) is a ribonucleic acid (RNA) virus with predominant fecal oral spread. Traditionally in Western Europe it is associated with travel to endemic countries, but an increasing number of locally acquired cases have been reported throughout England. Patients presenting with acute non-travel associated HEV infection in south Wales over a 25-month period were monitored, in an attempt to understand the clinical picture and epidemiology in our patient population. Twenty-four patients were identified with non-travel associated HEV infection and studied prospectively. Patient demographics, symptoms, and serial laboratory results were recorded. There was a male/female ratio of 3:1, with a median patient age of 65.5 years old. Patients developed a significant icteric hepatitis (median peak bilirubin: 139 µmol/L, median peak AST: 1,973 IU/L and ALT: 2,021 IU/L), with liver function remaining abnormal for ∼7 weeks. All patients in whom HEV RNA was isolated were infected with genotype 3. Forty-six percent of patients presented during winter months. The data show a group mortality rate of 4.2%, similar to that reported in endemic countries. HEV results in a severe and occasionally fatal hepatitis. Testing for hepatitis E is now recommended in any patient presenting with acute hepatitis of unknown etiology.

Epidemiology and risk factors of incident hepatitis E virus infections in rural Bangladesh

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis in the world. Most of South Asia is HEV endemic, with frequent seasonal epidemics of hepatitis E and continuous sporadic cases. This author group's epidemiologic work and clinical reports suggest that Bangladesh is HEV endemic, but there have been few population-based studies of this country's HEV burden. The authors calculated HEV infection rates, over an 18-month interval between 2003 and 2005, by following a randomly selected cohort of 1,134 subjects between the ages of 1 and 88 years, representative of rural communities in southern Bangladesh. Baseline prevalence of antibody to hepatitis E virus (anti-HEV) was 22.5%. Seroincidence was 60.3 per 1,000 person-years during the first 12 months and 72.4 per 1,000 person-years from >12 to 18 months (during the monsoon season), peaking by age 50 years and with low rates during childhood. Few of the seroconverting subjects reported hepatitis-like illness. Overall incidence was calculated to be 64 per 1,000 person-years, with 1,172 person-years followed. No significant associations were found between anti-HEV incidence and demographic or socioeconomic factors for which data were available. This is the first study to document annual HEV infection rates among "healthy" and very young to elderly subjects in a rural Bangladeshi population.

Clinical course and duration of viremia in vertically transmitted hepatitis E virus (HEV) infection in babies born to HEV-infected mothers

Infection with the hepatitis E virus (HEV) causes a self-limiting acute hepatitis. However, prolonged viremia and chronic hepatitis has been reported in organ transplant recipients. Vertically transmitted HEV infection is known to cause acute hepatitis in newborn babies. The clinical course and duration of viremia in vertically transmitted HEV infection in neonates in not known. We studied 19 babies born to HEV infected mothers. Babies were studied at birth and on a monthly basis to evaluate clinical profile, pattern of antibody response and duration of viremia in those infected with HEV. Fifteen (78.9%) babies had evidence of vertically transmitted HEV infection at birth (IgM anti-HEV positive in 12 and HEV RNA reactive in 10) and three had short-lasting IgG anti-HEV positivity because of trans-placental antibody transmission. Seven HEV-infected babies had icteric hepatitis, five had anicteric hepatitis and three had high serum bilirubin with normal liver enzymes. Seven babies died in first week of birth (prematurity 1, icteric HEV 3, anicteric HEV 2 and hyperbilirubinemia 1). Nine babies survived and were followed up for clinical, biochemical, serological course and duration of viremia. Five of 9 babies who survived were HEV RNA positive. HEV RNA was not detectable by 4 weeks of birth in three babies, by 8 weeks in one and by 32 weeks in one. All surviving babies had self-limiting disease and none had prolonged viremia. Thus HEV infection is commonly transmitted from mother-to-foetus and causes high neonatal mortality. HEV infection in survivors is self-limiting with short lasting viremia.

Hepatitis e: a UK perspective

Hepatitis E is increasingly recognized as a cause of viral hepatitis within the UK and should be considered in any patient presenting with acute hepatitis. Mortality rates of around 4% have been described, but are even higher during pregnancy.

Safety, immunogenicity, and antibody persistence of a new meningococcal group A conjugate vaccine in healthy Indian adults

We performed a double-blind, randomized, controlled phase I study to assess safety, immunogenicity, and antibody persistence of the new meningococcal group A conjugate vaccine (PsA-TT) in healthy volunteers aged 18-35 years. Of the 74 male subjects enrolled, 24 received the PsA-TT vaccine (Group 1), 25 received the Meningococcal Polysaccharide Vaccine A+C, Pasteur, Lyon, France (Group 2), and 25 received the Tetanus Toxoid Vaccine Adsorbed, SIIL, Pune India (Group 3). No immediate reactions were observed. Local and systemic solicited reactions within 7 days post-vaccination and unsolicited adverse events (AEs) were mild and similar among the three groups and resolved without sequelae. No serious AEs were notified up to 1 year post-vaccination. Four weeks post-vaccination, a slightly higher proportion of Group 1 subjects had a four-fold increase in SBA titers compared to Group 2 subjects (83% versus 72%, p>0.05). SBA GMTs in Groups 2 and 3 were higher than in Group 3 (p<0.05). Serogroup A-specific IgG GMCs were significantly higher in Group 1 than in Groups 2 (p<0.05) and 3 (p<0.05). After 1 year SBA titers were significantly higher in Group 1 than in Group 2 (p<0.05). The new PsA-TT vaccine was shown to be safe, immunogenic, and able to elicit persistent functional antibody titers in adults. This opens the prospective for further development and licensure of this vaccine to eliminate epidemic meningitis in sub-Saharan Africa.

Hepatitis E virus

Hepatitis E virus (HEV) is the aetiological agent of non-HAV enterically transmitted hepatitis. It is the major cause of sporadic as well as epidemic hepatitis, which is no longer confined to Asia and developing countries but has also become a concern of the developed nations. In the Indian subcontinent, it accounts for 30-60% of sporadic hepatitis. It is generally accepted that hepatitis E is mostly self-limited and never progresses to chronicity. It has a higher mortality in pregnant women where the disease condition is accentuated with the development of fulminant liver disease. Currently, no antiviral drug or vaccine is licensed for HEV, although a vaccine candidate is in clinical trials. HEV genome is 7.2kb in size with three open reading frames (ORFs) and 5' and 3' cis acting elements, which have important roles to play in HEV replication and transcription. ORF1 codes for methyl transferase, protease, helicase and replicase; ORF2 codes for the capsid protein and ORF3 for a protein of undefined function. HEV has recently been classified in the genus Hepevirus of the family Hepeviridae. There are four major recognised genotypes with a single known serotype. The absence of a reliable in vitro propagation system is an obstacle to deciphering HEV biology. The genome of HEV has been cloned, sequenced and the infectious nature of these replicons has been established. However, questions related to replication, transcription, virus-host interactions and pathogenesis remain to be answered. This comprehensive review summarises the progress made so far in HEV research, and addresses some of the unanswered questions.

Hepatitis E virus infection among animals in northern India: an unlikely source of human disease

Hepatitis E virus (HEV) is a major cause of acute hepatitis in many developing countries. Based on data from nonendemic regions, an animal reservoir of HEV has been proposed; however, data from HEV-endemic regions are limited. We tested sera from 200 pigs, 98 chickens, 86 goats, 58 sheep and 30 buffaloes for anti-HEV IgG using two different enzyme immunoassays. Specificity of the detected antibodies was confirmed using inhibition assays. Stool specimens from 210 pigs, 94 piglets and 37 sheep were tested for HEV-RNA using nested amplification methods; the polymerase chain reaction products were sequenced and compared with known human and swine HEV sequences. Of the 200 swine sera, 193 and 195, respectively, tested positive in the two assays. All goat sera showed anti-HEV reactivity in both the assays. Inhibition studies confirmed the HEV specificity of antibodies detected in swine and goat sera using both the assays. Sera from sheep, buffalo and chickens also showed high rates of apparent reactivity, but inhibition studies were unable to confirm the specificity of reactions in these species. One faecal specimen showed amplification using Indian swine HEV-specific primers. The genomic sequence of the amplicon from this isolate had only 76-79% nucleotide and 93% amino acid homology with human HEV isolates reported from India and other parts of the world, and most closely resembled swine HEV isolates from other parts of India. Infection with HEV or a related agent is widespread among animals in northern India. However, the swine HEV in India differs genetically from human HEV isolates, indicating that pigs may not play an important role in the spread of human hepatitis E in endemic regions.

Molecular detection and sequence analysis of a new hepatitis E virus isolate from Pakistan

Sporadic and epidemic acute viral hepatitis E in many developing countries is caused by hepatitis E virus (HEV). The HEV genome has been classified into three major genotypes. However, extensive diversity has been noted among HEV isolates from patients with acute hepatitis in China and Taiwan. Some reports indicated that multiple genotypes of HEV could cocirculate in the same area; even distinct genotypes of HEV could exist in the same patient. Pakistan is a highly endemic area for hepatitis E. So far only two Pakistan HEV isolates Sar-55 (87-Pakistan-A) and Abb-2B (88-Pakistan-2B) have been characterized, and the nucleotide sequences of these two HEV isolates show only 90% homology. In this study, a third HEV isolate from Pakistan (87-Pakistan-B) is reported. The sequences of a 438-bp fragment from ORF-2 and a 259-bp fragment from the ORF-1-3 region of this new HEV isolate were obtained and sequenced. The sequence analysis showed that this new HEV isolate was very closely related to the Sar-55 but different from the Abb-2B HEV isolate. These results indicated that the Sar-55 (87-Pakistan-A) genotype is the main endemic HEV strain in the Sargodha area. These data will be useful for HEV epidemiological studies, diagnosis and vaccine development.

Seroprevalence for hepatitis E virus (HEV) infection among volunteer blood donors of the Regional Blood Bank of Londrina, State of Paraná , Brazil

A cross-sectional study was carried out among 996 volunteer blood donors enrolled from May 1999 to December 1999 to determine the seroprevalence of hepatitis E virus (HEV) infection among volunteer blood donors of the Regional Blood Bank of Londrina, State of Paraná, Brazil, and to evaluate whether the rate of seroprevalence of IgG anti-HEV antibodies is associated with sociodemographic variables and with seropositivity for hepatitis A virus (HAV) infection. All participants answered the questionnaire regarding the sociodemographic characteristics. Serum samples were tested for IgG antibodies to HEV (anti-HEV) by an enzyme linked immunoassay (ELISA). All serum samples positive for anti-HEV IgG and 237 serum samples negative for anti-HEV were also assayed for IgG anti-HAV antibodies by ELISA. Anti-HEV IgG was confirmed in 23/996 samples, resulting in a seroprevalence of 2.3% for HEV infection, similar to previous results obtained in developed countries. No significant association was found between the presence of anti-HEV IgG antibodies and the sociodemographic variables including gender, age, educational level, rural or urban areas, source of water, and sewer system (p > 0.05). Also, no association with seropositivity for anti-HAV IgG antibodies was observed (p > 0.05). Although this study revealed a low seroprevalence of HEV infection in the population evaluated, the results showed that this virus is circulating among the population from Londrina, South Brazil, and point out the need of further studies to define the clinical and epidemiological importance of HEV infection and to identify additional risk factors involved in the epidemiology and pathogenesis of this infection in this population.

Hepatitis E virus infection may be transmitted through blood transfusions in an endemic area

AIM

To address the issue of whether or not hepatitis E virus (HEV) is transmitted parenterally.

METHODS

We conducted a retrospective study which involved 145 multiple transfused patients and 250 healthy controls. A prospective study was also undertaken involving 50 hospitalized patients, 25 of whom were transfused with 107 blood units, while the other 25 did not receive any transfusions.

RESULTS

In our retrospective study, markers of acute HEV infection (IgM anti-HEV and HEV RNA) were detected in a significantly higher number of multiple transfused patients (13 of 145) compared to controls (two of 250) (P < 0.001; OR = 12.21 [95% confidence interval: 2.71-54.70]). All 13 HEV-infected patients had been transfused at least once in a 3-month period before testing. Overall, patients positive for any of the HEV markers (IgG, IgM or HEV RNA) had received more blood transfusions, had higher occurrence of icteric disease and higher serum alanine aminotransferase levels. In our prospective study, IgG anti-HEV was detected in 11 of 107 donor samples, three of 25 patients in their pretransfusion samples (one sample was positive for IgM anti-HEV as well) and two of 25 control patients. Post-transfusion HEV infection developed in three of 22 susceptible (IgG anti-HEV negative) transfused patients; the infection was traced to their four respective donors who were asymptomatic, HEV RNA positive (4/4) and IgM anti-HEV positive (3/4). In contrast, none of the non-transfused patients developed HEV infection during the follow-up period.

CONCLUSION

Frequent transmission of HEV by blood transfusion places recipients at risk and warrants redefining of the donor screening policy by blood banks, especially in endemic areas.

Aetiology and prognostic factors in acute liver failure in India

The early prognostic indicators for acute liver failure in endemic zones for hepatitis E virus have not been determined. All consecutive patients with acute liver failure from a geographically defined region endemic for hepatitis E virus were studied over the period April 1989-April 1996. Demographic, clinical and biochemical parameters were recorded at presentation and serum samples were analysed for known viral hepatitis (A-E) markers. Multiple parameters were compared in survivors and non-survivors in a univariate analysis. All significant factors on univariate analysis were entered into a stepwise logistic regression analysis to identify independent variables of prognosis. The sensitivity and specificity of significant prognostic factors was then assessed. A total of 180 [69 males and 111 females: age (mean +/- SD) 31.1 +/- 14.7 years] with acute liver failure were studied. Of these, 131 (72.8%) patients died. Hepatitis E virus was the aetiological cause in 79 (43.9%) patients, while hepatitis A virus, hepatitis B virus, hepatitis C virus and non-A, non-E agent/'s could be incriminated in four (2.1%), 25 (13.9%), 13 (7.2%) and 56 (31.1%) patients respectively. Of 83 women in childbearing age, 49 (59.0%) were pregnant, 33 (67.3%) of these were in the third trimester. Forty-seven (95.8%) pregnant women had HEV infection. Nine variables differed significantly between survivors and non-survivors on univariate analysis. Of these, four variables which predicted the adverse outcome on multivariate analysis were non-hepatitis-E aetiology, prothrombin time >30 s, grade of coma >2 and age >40 years in that order of significance. Pregnancy per se or duration of gestation did not adversely affect the prognosis. In endemic areas, hepatitis E virus is the commonest cause of acute liver failure. Acute liver failure occurs in a high proportion of pregnant women, mostly in third trimester. Early predictors of a poor outcome are non-E aetiology, prothrombin time >30 s, grade of coma >2 and age >40 years.

Aetiology, clinical course and outcome of sporadic acute viral hepatitis in pregnancy

Hepatitis E causes large-scale epidemics in endemic areas. The disease, during epidemics, has increased incidence and severity in pregnant women. Sporadic acute viral hepatitis (AVH) is common in endemic areas. The relationship of sporadic AVH and pregnancy has not been well studied. Over a 3-year period we prospectively studied 76 pregnant women and 337 non-pregnant women of childbearing age with sporadic acute viral hepatitis for aetiology, clinical course and outcome of disease. The aetiology in sporadic AVH was hepatitis A virus (HAV) in six (1.5%), hepatitis B virus (HBV) in 62 (15%), hepatitis C virus (HCV) in seven (1.7%), hepatitis D virus (HDV) co-infection in six (1.5%), hepatitis E virus (HEV) in 205 (49.6%), and hepatitis non-A-to-E (HNAE) in 127 (30.7%). Sixty-five (85.5%) pregnant women and 140 (41.5%) nonpregnant women had hepatitis E. The proportion of pregnant women was 31.7% in HEV group and 5.3% in non-HEV group [P < 0.001; OR=8.3 (95%C1 4.2-16.3)]. The prevalence of HEV in pregnant women in first trimester (76.9%), second trimester (88.9%), third trimester (83.8%) and puerperium (100%) did not differ significantly (P=0.09). Forty-seven (61.8%) of the 76 pregnant women developed fulminant hepatic failure (FHF), 69.2% in HEV group and 10% in non-HEV group (P < 0.001). Thirty-four (10.1%) nonpregnant women developed fulminant hepatic failure, 10% in HEV group and 9.7% in non-HEV group (P=0.86). FHF had occurred in four (40%) of 10 patients with HE in first trimester as against 41 (74.5%) of 55 patients in second trimester and beyond (P=0.015). Amongst the major complications of fulminant hepatic failure, cerebral oedema (53.2%) and disseminated intravascular coagulation (21.3%) occurred more often in pregnant women than in nonpregnant women (29.4% and 2.8%; P=0.03 and 0.016, respectively) while infections occurred more often in nonpregnant women (36.1%) than in pregnant women (10.6%; P=0.003). Fifty (61.7%) patients with FHF died [25 (53.2%) pregnant women and 25 (69.5%) nonpregnant women (P=0.06)]. Cerebral oedema and HEV aetiology were independent variables of survival in patients with FHF. Patients with cerebral oedema had worse prognosis and patients with HEV aetiology had best chances of survival. Hence HEV was the most common cause of sporadic AVH in this endemic area. High proportion of pregnant women and increased severity of disease in pregnancy were limited to patients with hepatitis E. Sporadic AVH caused by agents other than HEV did not show any special predilection to or increased severity in pregnancy. FHF in pregnant women caused by HEV was an explosive disease with short pre- encephalopathy period, rapid development of cerebral oedema and high occurrence of disseminated intravascular coagulation and may represent a severe manifestation of a Schwartzmann-like phenomenon.

Hepatitis E virus superinfection in patients with chronic liver disease

Infection with hepatitis A virus (HAV) can cause severe illness in adult patients with chronic liver disease (CLD) caused by hepatitis C. In endemic areas such as South Asia, however, most adult patients already have been exposed to HAV but could still be susceptible to hepatitis E virus (HEV) infection. We document that HEV superinfection in 4 of our CLD patients caused severe liver decompensation. We then determined the seroprevalence of HAV and HEV in 233 patients with stable CLD, with the goal of defining the need for protection against these viruses in these patients. Overall, 41 (17.5%) of 233 CLD patients were HEV antibody immunoglobulin G (IgG)-positive, and 228 of 233 (97.8%) were HAV IgG-positive. As controls, we tested 90 age- and sex-matched healthy volunteer blood donors for HAV and HEV antibodies IgG. There was no difference in the percentage of CLD patients and blood donors positive for HEV antibody IgG (17.7% vs. 17.5%) or for HAV IgG (97.8% vs. 94%). No differences were observed in the severity of liver disease between previously HEV-exposed and -nonexposed patients. In conclusion, superinfection with HEV in patients with underlying CLD can cause severe hepatic decompensation leading to increased morbidity and mortality. The large majority of adult CLD patients in endemic countries are vulnerable to infection with HEV, but are protected against hepatitis A, and are ideal candidates for an HEV vaccine.

Role of hepatitis E and other hepatotropic virus in aetiology of sporadic acute viral hepatitis: a hospital based study from urban Delhi

Major hepatotropic virus continues to be an important cause of acute viral hepatitis (AVH) in developing countries like India. While epidemics of AVH have been well studied few serious sporadic cases from developing countries have been reviewed. We studied prospectively 75 cases of sporadic AVH who reported to our hospital and were evaluated for the presence of various hepatotropic viruses. The seroprevalence of IgG anti-HEV antibodies was studied in the general population as a control. We found 53.3% (40/75) of sporadic AVH cases were due to hepatitis E virus while 11% (8/75) were due to hepatitis B virus. Hepatitis C virus was responsible for 8% (6/75) of the sporadic AVH cases and hepatitis A was found in 5% (4/75) of the cases. No causative agent was found in 23% (17/75) of the sporadic AVH cases. The sporadic AVH cases due to HEV were not clinically or biochemically not different from AVH due to other viruses. We found a high prevalence of IgG anti-HEV in 35.6% (178/500) among the general population of urban Delhi. The study suggested that hepatitis E was the most common cause of sporadic AVH in urban Delhi. High seroprevalence of IgG anti-HEV antibodies in the general population and amongst the sporadic AVH cases suggests that it is unlikely to be protective antibody. IgM anti-HEV positive serology is considered diagnostic of acute hepatitis E infection in India, where hepatitis E is endemic.

Epidemiological characteristics, risk factors, and clinical manifestations of acute non-A-E hepatitis

A substantial proportion of acute non-A, non-B hepatitis was of unknown etiology and was termed non-A-E hepatitis. Analysis of the clinical features is needed while attempting to identify the causative agent(s). In this study, the clinical and biochemical features of 53 patients who were admitted to hospital with acute non-A-E hepatitis were compared with a cohort of patients with acute hepatitis C (n = 70) and E (n = 5). In acute non-A-E hepatitis, the sex ratio was 34:19, and ages ranged from 21 to 76 years (median 49). Biochemical tests [median (range)] revealed albumin 3.6 (2.2-4.4) g/dl, AST 714 (193-2311) U/l, ALT 896 (310-3,000) U/l, bilirubin 11.2 (0.9-36.3) mg/dl, and prothrombin time > 1.1 (0-11.5) seconds. No patients reported parenteral exposures or household contact. Forty-five percent had severe hepatitis (i.e., albumin < 3 g/dl, bilirubin > 15 mg/dl or prothrombin time > 3 sec), including 3% with fulminant hepatitis. Chronic evolution was noted in 7%. These features were similar to those of hepatitis C or E, except for a significantly high frequency of parenteral exposures (20%), household contact (16%), and chronicity (70%) in hepatitis C. In conclusion, there is no obvious parenteral risk factor identified in acute non-A-E hepatitis. Clinical severity is similar to that of hepatitis C at least in hospitalized patients, but the rate of chronic evolution is much lower.

Hepatitis E

Hepatitis E, previously known as enterically transmitted non-A, non-B hepatitis, is an infectious viral disease with clinical and morphologic features of acute hepatitis. Its causative agent, hepatitis E virus, consists of small, 32- to 34-nm diameter, icosahedral, nonenveloped particles with a single-stranded, positive-sense, 7.5-kb RNA. The virus has two main geographically distinct strains, Asian and Mexican; recently, novel isolates from nonendemic areas and a genetically related swine HEV have been described. HEV is responsible for large epidemics of acute hepatitis and a proportion of sporadic hepatitis cases in the Indian subcontinent, southeast and central Asia, the Middle East, parts of Africa, and Mexico. The virus is excreted in feces and is transmitted predominantly by fecal-oral route, usually through contaminated water. Person-to-person transmission is uncommon. Clinical attack rates are the highest among young adults. Recent evidence suggests that humans with subclinical HEV infection and animals may represent reservoirs of HEV; however, further data are needed. Diagnosis of hepatitis E is usually made by detection of specific IgM antibody, which disappears rapidly over a few months; IgG anti-HEV persists for at least a few years. Clinical illness is similar to other forms of acute viral hepatitis except in pregnant women, in whom illness is particularly severe with a high mortality rate. Subclinical and unapparent infections may occur; however, chronic infection is unknown. No specific treatment is yet available. Use of clean drinking water and proper sanitation is currently the most effective method of prevention. Passive immunization has not been proved to be effective, and recombinant vaccines for travelers to disease-endemic areas and for pregnant women currently are being developed.

Role of hepatitis E and other hepatotropic virus in aetiology of sporadic acute viral hepatitis: a hospital based study from urban Delhi

Major hepatotropic virus continues to be an important cause of acute viral hepatitis (AVH) in developing countries like India. While epidemics of AVH have been well studied few serious sporadic cases from developing countries have been reviewed. We studied prospectively 75 cases of sporadic AVH who reported to our hospital and were evaluated for the presence of various hepatotropic viruses. The seroprevalence of IgG anti-HEV antibodies was studied in the general population as a control. We found 53.3% (40/75) of sporadic AVH cases were due to hepatitis E virus while 11% (8/75) were due to hepatitis B virus. Hepatitis C virus was responsible for 8% (6/75) of the sporadic AVH cases and hepatitis A was found in 5% (4/75) of the cases. No causative agent was found in 23% (17/75) of the sporadic AVH cases. The sporadic AVH cases due to HEV were not clinically or biochemically not different from AVH due to other viruses. We found a high prevalence of IgG anti-HEV in 35.6% (178/500) among the general population of urban Delhi. The study suggested that hepatitis E was the most common cause of sporadic AVH in urban Delhi. High seroprevalence of IgG anti-HEV antibodies in the general population and amongst the sporadic AVH cases suggests that it is unlikely to be protective antibody. IgM anti-HEV positive serology is considered diagnostic of acute hepatitis E infection in India, where hepatitis E is endemic.