Hepatitis E virus: Western Cape, South Africa

Hepatitis E Seroprevalence and Detection of Genotype 3 Strains in Domestic Pigs from Sierra Leone Collected in 2016 and 2017

Hepatitis E virus (HEV) is the main cause of acute hepatitis in humans worldwide and is responsible for a large number of outbreaks especially in Africa. Human infections are mainly caused by genotypes 1 and 2 of the genus Paslahepevirus, which are exclusively associated with humans. In contrast, viruses of genotypes 3 and 4 are zoonotic and have their main reservoir in domestic and wild pigs, from which they can be transmitted to humans primarily through the consumption of meat products. Both genotypes 3 and 4 are widespread in Europe, Asia, and North America and lead to sporadic cases of hepatitis E. However, there is little information available on the prevalence of these genotypes and possible transmission routes from animal reservoirs to humans in African countries. We therefore analysed 1086 pig sera collected in 2016/2017 in four districts in Sierra Leone for antibodies against HEV using a newly designed in-house ELISA. In addition, the samples were also analysed for HEV RNA by quantitative real-time RT-PCR. The overall seroprevalence in Sierra Leone was low with only 44 positive sera and a prevalence of 4.0%. Two serum pools were RT-PCR-positive and recovered partial sequences clustered into the genotype 3 (HEV-3) of the order Paslahepevirus, species Paslahepevirus balayani. The results are the first evidence of HEV-3 infection in pigs from Sierra Leone and demonstrate a low circulation of the virus in these animals to date. Further studies should include an examination of humans, especially those with close contact with pigs and porcine products, as well as environmental sampling to evaluate public health effects within the framework of a One Health approach.

High seroprevalence of hepatitis E virus in the Free State province of South Africa

The seroepidemiology of hepatitis E virus (HEV) in South Africa is limited. We investigated anti-HEV IgM and IgG, in residual hepatitis A, B, and C negative serology specimens, at our public sector Free State (FS) laboratory. Of 299 specimens (01 May-31 October 2020), 182/299 (60.9%) had anti-HEV IgG and 1/299 (0.33%) had anti-HEV IgM. High HEV seroprevalence across different age groups suggests a different epidemiology in the FS, necessitating further research.

Contribution

The need for HEV research in South Africa is highlighted. Clinicians should consider HEV in their differential diagnosis of patients with hepatitis.

Characterization of a Near Full-Length Hepatitis E Virus Genome of Subtype 3c Generated from Naturally Infected South African Backyard Pigs

Eight genotypes of the hepatitis E virus (Orthohepevirus A; HEV) designated HEV-1 to HEV-8 have been reported from various mammalian hosts. Notably, domestic pigs and wild boars are the natural reservoirs of HEV-3 and HEV-4 genotypes with zoonotic propensity. Since HEV infection in domestic pigs is usually subclinical, it may remain undetected, facilitating zoonotic spillover of HEV to the exposed human populations. A previous study from our group in 2021, using deep sequencing of a pooled saliva sample, generated various swine enteric virus genomes, including a near full-length swine HEV genome (7040 nt; 97.7% genome coverage) from five-month-old grower pigs at a backyard pig farm in the uMgungundlovu District, KwaZulu-Natal, South Africa. In the present study, we describe the further characterization, including genotyping and subtyping of the swine HEV isolate using phylogenetics and ‘HEVnet Typing Tool’. Our analyses confirmed that the South African swine HEV genome characterized in this study belonged to HEV genotype 3 subtype 3c (HEV-3c). While HEV-3c infections in domestic pigs have been previously reported from Brazil, Germany, Italy, and the Netherlands, they only generated partial genome sequences of open reading frame 1 (ORF1) and/or ORF2. To our knowledge, this is the first near full-length swine HEV-3c genome generated from naturally infected domestic pigs (Sus scrofa domesticus) in South Africa. However, due to the gap in the information on the HEV-3c genome sequences in various geographical locations worldwide, including South Africa, the epidemiology of the South African swine HEV genome characterized in this study remains inconclusive. Molecular and genomic surveillance of HEV in domestic pig populations in South Africa would be useful to determine their prevalence, circulating subtypes, and zoonosis risk.

Hepatitis E in Sub Saharan Africa - A significant emerging disease

Hepatitis E is an emerging endemic disease found across the African continent, but there are clear differences in epidemiology between North Africa and countries south of the Sahara. In this systematic review, Google scholar and PubMed databases were searched for peer-reviewed articles on HEV epidemiology. Publications meeting our inclusion criteria were critically reviewed to extract consistent findings and identify knowledge gaps. Hepatitis E has been reported in 25 of the 49 countries in Sub Saharan Africa.

Mortality rates of 1–2% in the general population and ~ 20% in pregnant women. Outbreaks were closely linked to refugees and Internally Displaced Persons in camps which accounted for 50% of reported outbreaks. There was very little research and concrete evidence for sources of contamination and transmission routes. There are indications of zoonotic transmission of Hepatitis E Virus infection but further research in these fields is required.

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No data from 50% of African countries

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Outbreaks closely linked to refugee and IDP camps

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Little data on sources of HEV contamination

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Indications but little evidence of zoonotic transmission

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Low awareness amongst health professionals and general public

Seroprevalence of anti-hepatitis E antibodies and antigens among HIV-infected patients in Fars Province, southern Iran

Objective

HIV-infected patients have immunological and clinical features that might affect the pathogenesis, as well as the outcome of the HIV/HEV co-infection. The current study aimed to determine the seroprevalence of anti-HEV antibodies and HEV antigens among HIV-infected patients in Fars Province, Southwest Iran.

Methods

Blood samples (5 mL) were collected from 251 HIV-confirmed patients. Respective data, including patients’ demographic information, were obtained for each patient. The presence of HEV antigens and anti-HEV antibodies (IgG) were assessed by commercial ELISA kits, based on the manufacturers’ instructions.

Results

Out of 251 cases, 158 (62.9%) were male and 91 (36.3%) were female. Patients’ age varied from 14 to 83 (mean: 40 ± 9.7) years. Out of 251 HIV positive cases, 26 (10.4%) were positive for anti-HEV IgG antibodies and 6 (2.4%) were positive for HEV-antigens. Also, 2 (0.8%) of the patients were positive for both anti-HEV IgG antibodies and antigens. Statistical analysis revealed no significant association between sex and seropositivity to either HEV antigen or antibodies. Moreover, no significant association was seen between age and seropositivity to HEV antigen or antibody (P = 0.622 and 0.945, respectively).

Conclusion

Our results showed a relatively low prevalence of HEV-antibodies in HIV-infected patients, indicating that HIV positive patients may not be at greater risk of HEV infection than the general population. Moreover, HEV-antigen was detected in a few cases of HIV-infected individuals which indicate an acute or chronic HEV infection in these patients.

Prevalence and risks of hepatitis E virus infection in blood donors from the Western Cape, South Africa

BACKGROUND

Transfusion-transmitted hepatitis E virus (HEV) infection is a potential risk to recipients of blood transfusions. Infection with HEV poses a high risk to immunocompromised recipients with an increased likelihood of developing chronic infection. The aims of this study were to determine the prevalence of past and active HEV infections in donors from the Western Cape and to identify the risk factors associated with infection.

MATERIALS AND METHODS

We prospectively tested 10 250 blood donors for HEV infection. A risk factor sub-study investigated 250 donors who completed a questionnaire, and plasma samples were tested for HEV IgG antibodies and pooled for HEV RNA detection. The demographic and risk factors associated with HEV infection were assessed. The molecular study tested 10 000 individual donations using a commercial assay to detect viraemia. HEV viral load and genotype were also determined.

RESULTS

The overall anti-HEV IgG seroprevalence was 42·8% (107/250) among donors participating in the risk factor sub-study. The likelihood of past HEV infection was higher with an increase in age. Of the 10 000 donor samples individually tested for HEV RNA, one sample was positive with a viral load of 7·9 x 10⁴ IU/ml and belonged to HEV genotype 3.

CONCLUSION

We found a high seroprevalence of anti-HEV IgG but a low HEV RNA prevalence among donors in the Western Cape, South Africa. The study provides evidence for a potential risk of HEV contamination in the blood supply in South Africa. A cost-benefit analysis is needed before considering the introduction of routine donor screening in our setting.

Hepatitis E Virus Seroprevalence and Associated Risk Factors in Apparently Healthy Individuals from Osun State, Nigeria

Hepatitis E virus (HEV) infection is a major public health concern in low-income countries, yet incidence and prevalence estimates are often lacking. Serum (n = 653) and faecal (n = 150) samples were collected from apparently healthy individuals using convenience sampling technique in six communities (Ore, Oke-Osun, Osogbo, Ede, Esa-Odo, and Iperindo) from Osun State, Nigeria. Serum samples were analysed for total anti-HEV IgG/IgM and anti-HEV IgM using commercially available HEV ELISA kits. Total anti-HEV positive serum and all stool samples were analysed for HEV RNA by RT-PCR. Overall, 15.0% (n = 98/653) and 3.8% (n = 25/653) of the serum samples were positive for anti-HEV total and IgM antibodies, respectively. Total anti-HEV and IgM in Ore, Oke-Osun, Osogbo, Ede, Esa-Odo, and Iperindo was 21.0% (n = 13/62) and 3.2% (n = 2/62), 19.4% (n = 20/103) and 6.8% (n = 7/103), 11.4% (n = 12/105) and 2.9% (n = 3/105), 8.0% (n = 16/199) and 1.5% (n = 3/199), 22.0% (n = 22/100) and 10.0% (n = 10/100), and 17.9% (n = 15/84) and 0.0% (n = 0/84), respectively. All samples (stool and serum) were HEV RNA negative. Anti-HEV seroprevalence was associated with rural location, increasing age, alcohol consumption, and rearing of animals. This study demonstrated a high anti-HEV seroprevalence in Osun State, indicating the need to implement surveillance and asses the hepatitis E burden in Nigeria.

Hepatitis E: a largely underestimated, emerging threat

Hepatitis E virus has two distinct clinical and epidemiological patterns based on the varying genotypes. Genotypes 3 and 4 cause widespread, sporadic infection in high-income countries and are emerging as the most common type of viral hepatitis in much of Europe. These infections carry significant morbidity and mortality in the growing numbers of immunosuppressed patients or in patients with established liver disease. Furthermore the growing extra-hepatic associations of the virus, including neurological and kidney injury, suggest that it may have been misnamed as a 'hepatitis' virus. This review explores current understanding of the epidemiology, virology and clinical presentations of hepatitis E infection and identifies vulnerable patient groups, who are at serious risk from infection. Guidance is offered regarding the diagnosis, treatment and prevention of this growing public health hazard.

Human Immunodeficiency Virus Infected Patients are Not at Higher Risk for Hepatitis E Virus Infection: A Systematic Review and Meta-Analysis

Hepatitis E virus (HEV) infection is the most common cause of acute hepatitis in the world. It is not well established whether people infected with the human immunodeficiency virus (HIV) are more susceptible to infection with HEV than people not infected with HIV. Many studies have evaluated this relationship, although none are conclusive. The aim of this systematic review and meta-analysis was to assess whether patients with HIV infection constitute a risk group for HEV infection. A systematic review and meta-analysis was performed in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), to find publications comparing HEV seroprevalences among HIV infected and uninfected populations. The analysis was matched by sex, age and geographical area, and compared patients who live with HIV and HIV-negative individuals. The odds ratio (OR) for patients with HIV was 0.87 (95% CI: 0.74-1.03) in the fixed effects meta-analysis and 0.88 (95% CI: 0.70-1.11) in random effects, with I² = 47%. This study did not show that HIV infection was a risk factor for HEV infection when compared with those who are HIV-negative.

Integrated value-chain and risk assessment of Pig-Related Zoonoses in Ghana

The marked increase in the pig-trade in Ghana has raised concerns about increased transmission of related zoonotic diseases. A study on pig-related zoonoses along the pork value-chain was conducted in Greater Accra and Upper East Regions of Ghana. Results showed significant taenia (60%) and trichinella (8%) seroprevalence in pigs in Upper East with little evidence of transmission to humans. Sero-prevalence of HEV was high in both pigs (85%) and humans (37%). Sero-prevalence rates were significantly higher in Upper East than Greater Accra. Pig handlers in Accra had significantly higher sero-prevalence rates (58%) than other community members (18%) but there was no such association in the Upper East. Given the high rates of mortality, miscarriage and stillbirth associated with HEV in pregnancy, it is a cause for concern that 31% women of child-bearing age tested sero-positive for HEV.

Hepatitis E Infection in HIV-Infected Patients

BACKGROUND

The hepatitis E virus (HEV) represents a major cause of acute hepatitis worldwide. The majority of HEV cases occur in low-income countries, mainly Asia and Africa, where HEV causes large outbreaks associated with the consumption of contaminated water and high mortality in specific populations. In high-income countries, HEV infection is considered a zoonotic disease that is linked to the consumption of contaminated food. Although a high proportion of cases have self-limiting asymptomatic or subclinical infections, immunosuppression may modify the pathogenesis and clinical impact of this emerging disease.

RESULTS AND DISCUSSION

Here, we review the current knowledge about the epidemiology, diagnosis, clinical manifestations, management and prevention of HEV infection in HIV-infected subjects.

CONCLUSIONS

Despite the increasing knowledge about the pathogenesis, epidemiology and clinical impact of HEV infection, several major factors are faced by HIV-infected patients, including treatment recommendations, immunization and risk practices.

Hepatitis A and E virus infections have different epidemiological patterns in Rwanda

OBJECTIVES

To investigate the prevalence of anti-HAV and HEV markers in order to better understand spread of these two viruses among adults in Rwanda.

METHODS

Samples from 1045 and 1133 blood donors, healthy adults and liver disease patients were analysed for anti-HAV IgG and HEV markers respectively.

RESULTS

Anti-HAV was present in 96.9% (1013/1045), with proportions of immune persons increasing with age. HEV infection markers were detected in 11.9% (135/1133) without differences between the three categories. Seven persons had low levels of HEV RNA including four blood donors but none of the HEV strains could be sequenced. The highest prevalence of HEV markers was in farmers and persons from the Southern (17.3%) and Western regions (18.6%), which have the national highest density of pigs. This may indicate that pigs constitute an important source of HEV infection for humans in Rwanda.

CONCLUSION

HAV remains highly endemic in Rwanda, but there may now be a decline of exposure during childhood. HEV is also endemic in Rwanda, but has a moderate spread and may be transmitted by blood transfusion. Based on the geographical and occupational differences in HEV prevalence, a possible zoonotic transmission from pigs should be further explored.

Seroprevalence of Hepatitis E Virus Infection Among People Living With HIV in the Central African Republic

Background

Hepatitis E virus (HEV) is a waterborne virus that causes acute hepatitis in immunocompromised patients and those who are immunocompetent. Few cases of chronic HEV have been described in industrialized countries. The Central African Republic is 1 of the few countries in the world that is endemic for both HIV and HEV. The prevalence of HIV infection is estimated to be 4.9% among adults aged 15-49 years, and hepatitis E is epidemo-endemic. The aim of this study was to characterize the epidemiology of HEV infection in people living with HIV (PLHIV) in Bangui.

Methods

A cross-sectional study was conducted between April and September 2015 based on answers to a questionnaire, and blood samples were collected for determination of immunological markers by enzyme-linked immunosorbent assay and molecular tests.

Results

Of the 200 PLHIV included, 15 (7.5%) had the IgM that characterizes acute HEV infection; 8.9% were women, and 2.2% were men. The overall seroprevalence of IgG was 68% (48% women and 70.4% men), indicating that men are statistically significantly more exposed to HEV than women. HEV infection had no effect on transaminase or T-CD4+ lymphocyte cell levels. The origin of infection could not be identified.

Conclusions

The seroprevalence of HEV is very high among PLHIV and in the general population of Bangui. This must be taken into account in studies of the risk factors of PLHIV infected with HEV.

Transmission and Epidemiology of Hepatitis E Virus Genotype 3 and 4 Infections

Following the introduction of robust serological and molecular tools, our understanding of the epidemiology of zoonotic hepatitis E virus (HEV) has improved considerably in recent years. Current thinking suggests that consumption of pork meat products is the key route of infection in humans, but it is certainly not the only one. Other routes of infection include environmental spread, contaminated water, and via the human blood supply. The epidemiology of HEV genotype (gt)3 and gt4 is complex, as there are several sources and routes of infection, and it is likely that these vary between and within countries and over time.

EASL Clinical Practice Guidelines on hepatitis E virus infection

Infection with hepatitis E virus (HEV) is a significant cause of morbidity and mortality, representing an important global health problem. Our understanding of HEV has changed completely over the past decade. Previously, HEV was thought to be limited to certain developing countries. We now know that HEV is endemic in most high-income countries and is largely a zoonotic infection. Given the paradigm shift in our understanding of zoonotic HEV and that locally acquired HEV is now the commonest cause of acute viral hepatitis in many European countries, the focus of these Clinical Practice Guidelines will be on HEV genotype 3 (and 4).

Hepatitis E virus infection in HIV-infected patients: A large cohort study in Yunnan province, China

Hepatitis E virus (HEV) infection in immunocompromised patients often results in distinct outcome, compared to the infection in general population. This study aimed to investigate the prevalence, potential risk factors, and clinical features of HEV infection among HIV patients treated with antiretroviral therapy (ART) in Yunnan province, China. A total of 770 HIV-infected patients between May 2015 and February 2016 were enrolled in Yunnan, China. All patients received ART. All plasma samples were tested for anti-HEV IgG, anti-HEV IgM antibodies using ELISA kits, and HEV RNA by real-time qRT-PCR. Association between anti-HEV antibody positivity and demographic, clinical and laboratory measures was assessed in univariate and multivariate logistic regression models. Of the 770 HIV-infected patients, 342 patients (44.42%) were anti-HEV IgG antibody positive, and six patients (0.78%) were anti-HEV IgM antibody positive. None of the patients was HEV RNA positive, as tested in our assays. We found that age, gender, CD4 cell count, WHO stage, marital status, and total cholesterol levels were associated with HEV infection. We report a high seroprevalence rate and several potential risk factors of HEV infection in a large HIV cohort from Yunnan province in China. Further research on identification of the circulating HEV strains and the clinical outcome of this patient population is required.

Human immunodeficiency virus and liver disease: A comprehensive update

Among persons living with human immunodeficiency virus (HIV) infection, liver disease remains a major cause of morbidity and mortality. While the etiologies are varied and often overlapping in the individual patient, the underlying mechanisms, including oxidative stress, direct activation of stellate cells, HIV interaction with hepatocytes, and bacterial translocation with systemic immune activation, seem to be unifying characteristics. Early and fully suppressive HIV antiretroviral therapy is a mainstay of management either before or concurrent with treatment of etiologic cofactors, including hepatitis C virus, hepatitis B virus, and nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Significant barriers to care that still exist include liver disease recognition, appropriate linkage to care, ongoing substance abuse, and psychiatric comorbidities in the HIV-infected population. Emerging issues in these patients include acute and chronic hepatitis E, underreported hepatitis D, and a rising incidence of hepatocellular carcinoma. (Hepatology Communications 2017;1:987-1001).

Racial differences in seroprevalence of HAV and HEV in blood donors in the Western Cape, South Africa: a clue to the predominant HEV genotype?

Hepatitis E virus (HEV) infection is a major cause of acute hepatitis worldwide. This infection causes major water-borne outbreaks in low- and middle-income countries, whilst in industrialised countries this infection is zoonotic. These differences in epidemiology are related to different HEV genotypes. HEV genotype 3 is a zoonotic infection, whilst genotype 2 causes large outbreaks. This study determined the seroprevalence of HEV in blood donors from the Western Cape. Anti-hepatitis A virus (anti-HAV) antibody was detected in 184/300 (61%) donors. Antibody to HEV (anti-HEV) was detected in 78 of 300 donors (26%). It was highest in mixed race donors (62/100), followed by white donors (23/100) and lowest in black donors (19/100) P = 0.019. Since it is thought that genotypes 1 and 2 predominate both viruses would be acquired by the oro-faecal route, it is surprising that HEV seroprevalence does not mirror that of HAV. We postulate that this may reflect differences in socio-economic status and consumption of dietary meat. So the marked divergence between HEV and HAV seroprevalence may be the result of different routes of transmission. Further data are needed to explore the risk factors associated with HEV infection.