Investigating an outbreak of acute viral hepatitis caused by hepatitis E virus variants in Karachi, South Pakistan

Genotypic analysis of hepatitis E virus (HEV) from sporadic symptomatic cases in Pakistan

Pakistan is the fifth most populous nation in the world and faces several challenges, including devastating floods, sub-optimal sanitary conditions, clustered accommodations, and unregulated cross-border movements. These drastic population shifts make it vulnerable to the efficient spread of the Hepatitis E virus (HEV). The current study analyzed the genotypic characteristics and variants of the Hepatitis E virus circulating in the population of Pakistan. A total of 75 ELISA-IgM positive samples were collected from three metropolitan cities: Lahore, Peshawar, and Karachi, and subjected to viral RNA extraction. The amplification of the HEV RNA-dependent RNA polymerase (RdRp) region was done using Nested PCR and degenerate primers. Out of the total, 40% of the samples were positive for HEV RNA. Sequencing and phylogenetic analysis identified the new HEV isolates as Subtype 1 g, a subtype within an existing HEV genotype 1. This shift warrants investigation into its impact on clinical manifestation and disease severity. Importantly, this study marks the first HEV subtype analysis in Pakistan, contributing valuable insights into subtype diversity and prevalence in the region.

Hepatitis A in the Eastern Mediterranean Region: a comprehensive review

INTRODUCTION

With 583 million inhabitants, the Eastern Mediterranean Region (EMR) is a worldwide hub for travel, migration, and food trade. However, there is a scarcity of data on the epidemiology of the hepatitis A virus (HAV).

METHODS

The MEDLINE and grey literature were systematically searched for HAV epidemiological data relevant to the EMR region published between 1980 and 2020 in English, French, or Arabic.

RESULTS

Overall, 123 publications were extracted. The proportion of HAV cases among acute viral hepatitis cases was high. HAV seroprevalence rate ranged from 5.7% to 100.0% and it was decreasing over time while the average age at infection increased.

CONCLUSION

In the EMR, HAV remains a significant cause of acute viral hepatitis. The observed endemicity shift will likely increase disease burden as the population ages. Vaccinating children and adopting sanitary measures are still essential to disease prevention; vaccinating at-risk groups might reduce disease burden even further.

Establishment of competitive binding assay to detect and differentiate hepatitis E virus infection

INTRODUCTION AND OBJECTIVES

This study was undertaken to demonstrate a promising approach for detection and differentiation the serum immunoglobulin G (IgG) against hepatitis E virus (anti-HEV IgG) using a competitive binding assay established with known genotype-specific monoclonal antibodies (mAbs) 2B1 and 4C5.

MATERIALS AND METHODS

The mAb 2B1 derived from genotype 1 hepatitis E virus (HEV) antigen and specifically reacted with genotype 1, 2 antigens; 4C5 induced by genotype 4 HEV antigen was specific to genotypes 3, 4 antigens. The 2B1 and 4C5 were labeled with Horseradish peroxidase (HRP), respectively. Subsequently, the titers of coated antigens and HRP-conjugated mAbs for establishment of competitive binding assay were determined by enzyme linked immunosorbent assay (ELISA). And then, the competitive binding assay was performed to assess the inhibition percentage of mAbs binding to antigens inhibited by different genotypes anti-HEV IgG.

RESULTS

The results of competitive binding assay revealed that genotype 1 anti-HEV IgG could inhibit the binding of mAb 2B1 to genotype 1 antigen more strongly than that of mAb 4C5 to genotype 4 antigen. Whereas, the genotype 3 or 4 anti-HEV IgG could inhibit the binding of mAb 4C5 to genotype 4 antigen more remarkably than that of mAb 2B1 to genotype 1 antigen.

CONCLUSIONS

These findings provided us a valuable approach for detection and differentiation the HEV infection derived from genotypes 1, 2 (human) or genotypes 3, 4 (zoonosis).

Clinical significance of post-liver transplant hepatitis E seropositivity in high prevalence area of hepatitis E genotype 3: a prospective study

High hepatitis E (HEV) seroprevalence has been reported in the general population and in post-liver transplant (LT) cases in several regions, including Thailand, with genotype 3 being a predominant genotype. We hypothesized that HEV might persist at a subclinical level and might pose clinical risks in the post-LT period. We performed a cross-sectional study with 108 post-LT patients and found an IgG seroprevalence of 55.6%. Subsequently, 91 cases without clinical evidence of HEV-related hepatitis were enrolled in 1 year of prospective follow-up to determine clinical status, serologies and serum/feces HEV RNA every 4 months. HEV RNA was detected, indicating subclinical infections in patients with or without seropositivity, with an annual incidence of 7.7%. Our results suggest that subclinical HEV infection exists among LT patients in this high-prevalence area. Thus, clinicians should be aware of the possibility of disease reemergence and HEV viral transmission in LT patients.

Implications of Hepatitis E Virus in Blood Transfusions, Hemodialysis, and Solid Organ Transplants

Hepatitis E Virus (HEV) is emerging as the primary cause of acute viral hepatitis in humans. The virus is commonly transmitted by the fecal-oral route via contaminated water in endemic regions or through the consumption of inadequately cooked swine products or game meats in industrialized regions. HEV genotypes 1 and 2 are predominantly associated with waterborne transmission in developing countries, whereas HEV3 and HEV4 are mainly zoonotically transmitted in industrialized countries. Seroprevalence in populations determined by detecting anti-HEV antibodies and serum HEV RNA is commonly used to analyze the presence of HEV. Although HEV RNA-based detection is now standardized, there is a lack of agreement between the assaying methods used for gathering seroprevalence data. Since 2004, HEV has been considered as a transmissible infectious agent through blood transfusion. Recent seroprevalence studies in European countries indicate an underestimated risk for blood transfusion and hence warrant testing the blood supply. HEV infection is usually self-limiting and spontaneously cleared. However, in about 60% of recipients of solid organ transplants, HEV progresses to chronic hepatitis. Immunosuppressive drugs such as tacrolimus are a major cause of chronic hepatitis and reducing its dosage results in viral clearance in about 30% of patients. In hemodialysis patients, the parenteral route is implicated as an important mechanism of transmission. In this review, we explore the clinical and epidemiological characteristics of various HEV genotypes in blood donors, hemodialysis patients, and transplant recipients.

Liver diseases in the Asia-Pacific region: a Lancet Gastroenterology & Hepatology Commission

The Asia-Pacific region is home to more than half of the global population and accounted for 62·6% of global deaths due to liver diseases in 2015. 54·3% of global deaths due to cirrhosis, 72·7% of global deaths due to hepatocellular carcinoma, and more than two-thirds of the global burden of acute viral hepatitis occurred in this region in 2015. Chronic hepatitis B virus (HBV) infection caused more than half of the deaths due to cirrhosis in the region, followed by alcohol consumption (20·8%), non-alcoholic fatty liver disease (NAFLD; 12·1%), and chronic infection with hepatitis C virus (HCV; 15·7%). In 2015, HBV accounted for about half the cases of hepatocellular carcinoma in the region. Preventive strategies for viral hepatitis-related liver disease include increasing access to clean drinking water and sanitation. HBV vaccination programmes for neonates have been implemented by all countries, although birth-dose coverage is extremely suboptimal in some. Availability of screening tests for blood and tissue, donor recall policies, and harm reduction strategies are in their initial stages in most countries. Many governments have put HBV and HCV drugs on their essential medicines lists and the availability of generic versions of these drugs has reduced costs. Efforts to eliminate viral hepatitis as a public health threat, together with the rapid increase in per-capita alcohol consumption in countries and the epidemic of obesity, are expected to change the spectrum of liver diseases in the Asia-Pacific region in the near future. The increasing burden of alcohol-related liver diseases can be contained through government policies to limit consumption and promote less harmful patterns of alcohol use, which are in place in some countries but need to be enforced more strictly. Steps are needed to control obesity and NAFLD, including policies to promote healthy lifestyles and regulate the food industry. Inadequate infrastructure and insufficient health-care personnel trained in liver diseases are issues that also need to be addressed in the Asia-Pacific region. The policy response of most governments to liver diseases has thus far been inadequate and poorly funded. There must be a renewed focus on prevention, early detection, timely referral, and research into the best means to introduce and improve health interventions to reduce the burden of liver diseases in the Asia-Pacific region.

Occurrence of microbial indicators, pathogenic bacteria and viruses in tropical surface waters subject to contrasting land use

Fecal indicator bacteria, such as Escherichia coli (E.coli) and Enterococcus, have been widely used to indicate the presence of pathogens. However, the suitability of fecal indicator bacteria to represent health risks is still being challenged, particularly in tropical aquatic environments. The objective of this study is to understand the occurrence and prevalence of indicators and pathogens in areas with contrasting land use, as well as to identify the major correlations between indicators, pathogens and environmental parameters. The spatial and temporal variation of indicators and pathogens was studied to examine the distribution patterns for areas with different land use, and the impact of seasonal changes on microbial populations. A total of 234 water samples were sampled for two years from reservoirs and their tributaries, and tested for fecal indicator bacteria, coliphages, human specific markers, pathogenic bacteria and viruses. The prevalence of indicators and pathogens in reservoirs were generally low, while relatively high concentrations were observed in tributaries to varying degrees. Of the enteric viruses, norovirus GII was among the most prevalent and had the highest concentration. Although strong correlations were found between indicators, only relatively weak correlations were found between indicators and pathogens. The results in this study showed that none of the bacteria/phage indicators were universal predictors for pathogens. Inclusion of the alternative indicators, Methanobrevibacter smithii, Bacteroides and human polyomaviruses (HPyVs) to monitoring programs could help to determine whether the fecal source was human. The microbial distribution patterns allow the classification of sampling sites to different clusters and thus, help to identify sites which have poor water quality. This approach will be useful for water quality management to pinpoint factors that influence water quality and help to prioritize sites for restoration of water quality.

Tracing the epidemic history of hepatitis C virus genotypes in Saudi Arabia

HCV genotype 4 is highly prevalent in many Middle Eastern countries, yet little is known about the genotype's epidemic history at the subtype-level in this region. To address the dearth of data from Saudi Arabia (SA) we genotyped 230 HCV isolates in the core/E- and NS5B-region and analyzed using Bayesian phylogenetic approaches. HCV genotype 4 (HCV/4) was positive in 61.7% (142/230) of isolates belonging to 7 different subtypes with the predominance of 4d (73/142; 51.4%) followed by 4a (51/142; 35.9%). Phylogenetic analysis also revealed a distinct epidemiological cluster of HCV/4d for Saudi Arabia. HCV/1 appeared as the second most prevalent genotype positive in 31.3% (72/230) of isolates with the predominance of 1b (53/72; 73.6%) followed by 1a (16/72; 22.2%), and 1g (3/72; 4.1%). A small proportion of isolates belonged to HCV/3a (12/230; 5.2%), and HCV/2a (4/230; 1.7%). We estimate that the genotype 4 common ancestor existed around 1935 (1850-1985). Genotype 4 originated plausibly in Central Africa and multiple subtypes disseminated across African borders since ~1970, including subtype 4d which dominates current HCV infections in Saudi Arabia. The Bayesian skyline plot (BSP) analysis showed that genotype 4d entered the Saudi population in 1900. The effective number of HCV infections grew gradually until the second half of the 1950s and more rapidly until the early-80s through the use of imported blood units and blood products. Subsequently, the rate of HCV infection in the Saudi Arabian population was stabilized through effective screening of blood and infection control measures.

Hepatitis E infection among Ghanaians: a systematic review

Background

Hepatitis E virus (HEV) infection is considered to be of significant public health importance in many developing countries. In this review, we aim to summarise studies on HEV with the aim of providing a further understanding of the epidemiology of the disease in Ghana.

Methods

A systematic review was conducted by following the recommendations outlined in the PRISMA statement. Studies on HEV infection among Ghanaians were identified by searching for articles (published up until 4th August 2016) in the PubMed, ISI Web of Science, African Journals Online, Google Scholar and the WHO African Index Medicus databases. We also searched the websites of the Ministry of Health and the Ghana Health Service to identify any related non-indexed studies. References of all retrieved studies were screened to identify additional publications.

Results

Ten studies involving a total of 2 894 participants from six regions of Ghana were identified. The proportion of Ghanaians showing positive serological markers for HEV infection was within the range of 5.8–71.55%. In addition, 0.7–45.9% tested positive for IgM antibodies while the proportion of Ghanaians testing positive for IgG antibodies was within the range of 0–45.3%. One study reporting a case fatality rate of 66.7% among pregnant women was identified. No information on HEV genotypes was retrieved.

Conclusions

Although based on a limited number of studies, this review does highlight that there is a high level of HEV infection among Ghanaians. Preventive measures including educational interventions as well as general improvements to sanitary and living conditions are needed to reduce the burden of the disease. Additionally, further research regarding the contribution of the various HEV genotypes is urgently needed to fully understand the burden of this disease in Ghana.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0239-9) contains supplementary material, which is available to authorized users.

A Nationwide Survey of Hepatitis E Virus Infection and Chronic Hepatitis E in Liver Transplant Recipients in Japan

Background

Recently, chronic hepatitis E has been increasingly reported in organ transplant recipients in European countries. In Japan, the prevalence of hepatitis E virus (HEV) infection after transplantation remains unclear, so we conducted a nationwide cross-sectional study to clarify the prevalence of chronic HEV infection in Japanese liver transplant recipients.

Methods

A total of 1893 liver transplant recipients in 17 university hospitals in Japan were examined for the presence of immunoglobulin G (IgG), IgM and IgA classes of anti-HEV antibodies, and HEV RNA in serum.

Findings

The prevalence of anti-HEV IgG, IgM and IgA class antibodies was 2.9% (54/1893), 0.05% (1/1893) and 0% (0/1893), respectively. Of 1651 patients tested for HEV RNA, two patients (0.12%) were found to be positive and developed chronic infection after liver transplantation. In both cases, HEV RNA was also detected in one of the blood products transfused at the perioperative period. Analysis of the HEV genomes revealed that the HEV isolates obtained from the recipients and the transfused blood products were identical in both cases, indicating transfusion-transmitted HEV infection.

Interpretation

The prevalence of HEV antibodies in liver transplant recipients was 2.9%, which is low compared with the healthy population in Japan and with organ transplant recipients in European countries; however, the present study found, for the first time, two Japanese patients with chronic HEV infection that was acquired via blood transfusion during or after liver transplantation.

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We conducted the multicenter survey for HEV infection in liver transplant recipients.

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Though the chronic HEV infection is rare, transfusion-transmitted cases were detected.

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Blood products can be a risk of chronic HEV infection in transplant recipients.

Viral Hepatitis in Pakistan: Past, Present, and Future

Viral hepatitis is a major cause of morbidity and mortality worldwide and a rising cause for concern in Asian countries. Weather it is blood borne or water/food borne hepatotropic virus, increasing burden is alarming for Asian countries. In this review we have evaluated the existing data to estimate the burden of viral hepatitis in populations of all age groups nationwide, along with an assessment of the risk factors and preventive and management strategies currently employed in Pakistan. The aim of our work is to consolidate and supplement the present knowledge regarding viral hepatitis in light of past and present trends and to provide future direction to the existing health policies.

How to cite this article

Butt AS, Sharif F. Viral Hepatitis in Pakistan: Past, Present, and Future. Euroasian J Hepato-Gastroenterol 2016;6(1):70-81.

Hepatitis E Virus Seroprevalence Rate in HIV-Infected Patients in Germany: A Comparison of Two Commercial Assays

OBJECTIVES

Cases of chronic hepatitis E virus (HEV) infection have been described in HIV-infected patients. There are several commercial anti-HEV assays, but anti-HEV seroprevalence rates differ largely depending on the assay used. The aim of this study was to (1) compare two commercial anti-HEV assays in a German cohort of HIV-positive individuals, and (2) determine whether HEV takes chronic courses in controlled HIV infection.

METHODS

246 HIV patients were tested for both HEV RNA and HEV antibodies. All patients received antiretroviral therapy, if this was indicated, according to European guidelines. All but 19 individuals had CD4+ counts above 200/µl. Anti-HEV IgG was determined by two independent commercial assays (Wantai and MP).

RESULTS

None of the patients tested HEV RNA positive. Anti-HEV IgG was detected more frequently by the Wantai assay (26%) than the MP assay (1.6%, p < 0.001). Patients born in Europe tested more frequently positive for anti-HEV (p = 0.047) than individuals from other regions. Increasing age but not CD4 count correlated with a higher likelihood of anti-HEV positivity (R = 0.313, p < 0.001).

CONCLUSIONS

About one quarter of HIV-infected patients show evidence of previous HEV contact. The risk of developing chronic HEV infection is very low in individuals receiving appropriate antiretroviral therapy. The large variability in HEV seroprevalence rates determined by different assays requires consideration for the diagnostic workup of HIV patients.

Hepatitis E as a cause of acute jaundice syndrome in northern Uganda, 2010-2012

Hepatitis E virus (HEV) is a common cause of acute viral hepatitis in developing countries; however, its contribution to acute jaundice syndrome is not well-described. A large outbreak of hepatitis E occurred in northern Uganda from 2007 to 2009. In response to this outbreak, acute jaundice syndrome surveillance was established in 10 district healthcare facilities to determine the proportion of cases attributable to hepatitis E. Of 347 acute jaundice syndrome cases reported, the majority (42%) had hepatitis E followed by hepatitis B (14%), malaria (10%), hepatitis C (5%), and other/unknown (29%). Of hepatitis E cases, 72% occurred in Kaboong district, and 68% of these cases occurred between May and August of 2011. Residence in Kaabong district was independently associated with hepatitis E (adjusted odds ratio = 13; 95% confidence interval = 7-24). The findings from this surveillance show that an outbreak and sporadic transmission of hepatitis E occur in northern Uganda.

Hepatitis E seroprevalence among blood donors: A pilot study from Western India

Background:

Hepatitis E virus (HEV) is emerging as a potential threat to blood safety after several cases of transmission by transfusion or transplantation have been described. Currently, blood donors in India are not screened for HEV. The studies conducted on HEV in recent times in India have focused on epidemiology and future perspectives, but there is no published study on blood donors. To address possible issues surrounding blood safety and risk of HEV transmission within the Indian blood supply, HEV seroprevalence study was conducted in blood donors at our center.

Materials and Methods:

A total of 460 male voluntary blood donors were selected for the study and after taking their written consent. Serum anti-HEV IgM was detected by Dia.Pro HEV kit (Diagnostic Bioprobes Srl, Milano, Italy).

Results:

The study population was composed of 460 male voluntary blood donors and their age ranged from 18 to 60 years with a mean age of 30.48 years. Out of 460 donors, 22 (4.78%) donors were tested positive for IgM anti-HEV and the mean value alanine aminotransferase (ALT) was 26.06 IU/L, the highest being 93.5 IU/L. Normal reference value of ALT in our center was 40 IU/L. Out of 22 anti-HEV positive donors, 19 (86.36%) had ALT values above 40 IU/L.

Conclusion:

HEV seroprevalence of 4.78% in our center. Though reports of HEV transmission through blood has been reported from various parts of the world, before making it as a mandatory screening test among blood donors in India, further studies with confirmatory assay of HEV need to be done.

Performance of anti-HEV assays for diagnosing acute hepatitis E in immunocompromised patients

Hepatitis E virus is an emerging concern in immunocompromised patients, who may become chronically infected. This prompted us to assess the performance of two anti-HEV IgG and IgM assays for diagnosing acute HEV infections. The specificities of the assays were estimated by testing samples from 2 to 3 year-old French children and blood donors and their sensitivities by testing 40 immunocompromised patients acutely infected. Both anti-HEV IgM assays were highly specific (99.6% and 100%). The sensitivity of the Adaltis was 87.5%, and that of Wantai was 85%. The specificities of anti-HEV IgG Wantai (97.8%) and Adaltis tests (89.5%, p=0.1) were similar but the Wantai test was more sensitive (45%) than the Adaltis test (15%, p<0.001). None of the samples was anti-HEV IgM negative and IgG positive. We conclude that these anti-HEV IgM assays performed well in immunosuppressed subjects with acute hepatitis E and can be used as first line virological tools. Testing for anti-HEV IgG and IgM simultaneously at the acute phase did not improve the diagnostic performance. In contrast, molecular detection of HEV RNA appears essential to exclude an HEV infection in patients who are negative for anti-HEV IgM and to assess the evolution of hepatitis E 3 months thereafter.

Seroprevalence of anti-hepatitis E virus (HEV) in a Korean population: comparison of two commercial anti-HEV assays

Background

Hepatitis E virus (HEV) has emerged as an important cause of epidemic and sporadic acute viral hepatitis worldwide. This study investigated the seroprevalence of anti-HEV in a Korean population and compared the performance of two commercially available anti-HEV assays.

Methods

A total 147 health-check examinees were randomly sampled as matched to the age- and sex- adjusted standard population based on the Korean National Census of 2007. Serum immunoglobulin G anti-HEV was determined by using the Genelabs assay (Genelabs, Singapore) and the Wantai assay (Wantai, Beijing, China).

Results

The overall anti-HEV seroprevalence was 23.1% (95% CI, 16.1-30.1%) using the Wantai assay and 14.3% (95% CI, 8.3-20.3%) using the Genelabs assay. Only 12 samples (8.1%) were positive for anti-HEV as measured by both assays; agreement between the two assays was poor (kappa value of 0.315). The anti-HEV seroprevalence increased with age from 2% and 3% in the people younger than 20-years-of-age to 34.6% and 42.3% in those over 59-years-of-age by the Genelabs and Wantai assay, respectively.

Conclusions

The HEV seroprevalence in Korean population is about 20% overall, with seroprevalence increasing in this population with increasing age. There was poor concordance in the results of the Genelabs and Wantai assays, which warrants further study concerning a reliable diagnostic test for the diagnosis of hepatitis E.

Prevalence of antibodies and RNA genome of hepatitis E virus in a cohort of French immunocompromised

BACKGROUND

Recently, cases of chronic hepatitis E have been identified in immunocompromised patients.

OBJECTIVES

To evaluate the prevalence of anti-HEV IgG antibodies and the persistence of HEV-RNA in sera of immunocompromised patients with regular follow-up at Saint-Louis Hospital in Paris, France.

STUDY DESIGN

307 samples collected from 261 HIV-infected patients and 46 kidney transplant (KT)-patients were retrospectively tested for the presence of the following hepatitis E virus (HEV) infection markers: anti-HEV IgM antibodies, anti-HEV IgG antibodies, anti-HEV IgG avidity index, and HEV-RNA.

RESULTS

Anti-HEV IgG positive serology was found in 4 HIV-infected patients (1.5%) and 3 KT-patients (6.5%), leading to an overall seroprevalence of 2.3%. HEV-RNA detection was not observed among 55 HIV-patients at higher risk of chronic HEV (<200 CD4 cells/mm(3), elevated alanine aminotransferase (ALT) levels, and/or positive anti-HEV antibodies) and among 44 KT-patients. None of the seven patients had anti-HEV IgM antibodies, thereby excluding any acute infection. The IgG avidity index confirmed past HEV infection among tested patients.

CONCLUSIONS

The low seroprevalence observed in the Paris region does not warrant a systematic evaluation of HEV infection in immunocompromised patients. However, HEV infection must be examined as a possibility if unexplained increases in ALT should occur and after more common viral hepatitis infections are excluded.