Hepatitis E virus infection in Latin America: a review

Unraveling swine hepatitis E in the central region of Argentina through ELISA development and epidemiological insights

Hepatitis E virus (HEV) is a public health concern globally, causing acute viral hepatitis in humans. Genotype-3 HEV (HEV-3), the most frequently genotype detected in South America, is zoonotic and the main reservoirs are the domestic pig and wild boar. Circulation of HEV-3 in Argentina has been confirmed in humans as well as in pig herds, wild boar and environmental waters. However, data are scarce mainly due to the inaccessibility of serological assays in this country. In order to provide insights in the epidemiology of HEV in swine in Argentina, we developed an indirect ELISA based on the native recombinant protein ORF2 and conducted a serological survey to determine the prevalence of seropositive swine in small-scale pig farms in the central region of Argentina. The method was evaluated in a panel of 157 serum samples, resulting in relative sensitivity of 98.6 % (95 % CI 95 %-100 %) and relative specificity of 97.7 % (95 % CI 94 %-100 %) compared to a commercial test. An almost perfect agreement was obtained between the two tests (Kappa index of 0.961). A survey on 294 samples from 49 small-scale farms resulted in a seropositivity rate of 54 %. Seropositive animals were found in 34 out of 49 (69.4 %) farms. Most of the farms (70.6 %) had over 50 % of seropositive animals. The wide spreading of HEV in the swine population of Tandil, Argentina, underscore the need to better understand the epidemiology of HEV in the region, enabling the implementation of targeted interventions to mitigate the impact of this virus on public health.

Hepatitis E Virus (HEV) Synopsis: General Aspects and Focus on Bangladesh

HEV is the most common cause of acute hepatitis globally. This review summarizes the latest knowledge on the epidemiology, clinical characteristics, testing, and treatment of HEV infection. We also focused on Bangladesh to highlight the distinct challenges and the possible remedies. In low-income settings, the virus is mainly transmitted between people by fecal contamination of drinking water causing large outbreaks, and sporadic cases. The disease is usually mild and self-limiting acute hepatitis. Still, pregnant women and their offspring in low-income countries are at particular risk for severe disease, with up to 20% maternal mortality. Despite the high burden of the disease, HEV remains a relatively neglected virus, with detection hampered by costly tests and a lack of suitable treatments. Molecular PCR diagnostics, together with ELISA antibody tests, remain the preferred methods for diagnosis of HEV; however, rapid bedside diagnostics are available and could offer a practical alternative, especially in low-income countries. One vaccine (HEV 239) is only available in China and Pakistan, as efficacy against the other genotypes remains uncertain. The effectiveness trial conducted in Bangladesh might lead the way in gathering more efficacy data and could, together with improved surveillance and raised awareness, dramatically reduce the global burden of HEV.

Drug-induced liver injury: A management position paper from the Latin American Association for Study of the liver

Idiosyncratic drug-induced liver injury (DILI) caused by xenobiotics (drugs, herbals and dietary supplements) is an uncommon cause of liver disease presenting with a wide range of phenotypes and disease severity, acute hepatitis mimicking viral hepatitis to autoimmune hepatitis, steatosis, fibrosis or rare chronic vascular syndromes. Disease severity ranges from asymptomatic liver test abnormalities to acute liver failure. DILI has been traditionally classified in predictable or intrinsic (dose-related) or unpredictable (not dose-related) mechanisms. Few prospective studies are assessing the real prevalence and incidence of hepatotoxicity in the general population. DILI registries represent useful networks used for the study of liver toxicity, aimed at improving the understanding of causes, phenotypes, natural history, and standardized definitions of hepatotoxicity. Although most of the registries do not carry out population-based studies, they may provide important data related to the prevalence of DILI, and also may be useful to compare features from different countries. With the support of the Spanish Registry of Hepatotoxicity, our Latin American Registry (LATINDILI) was created in 2011, and more than 350 DILI patients have been recruited to date. This position paper describes the more frequent drugs and herbs-induced DILI in Latin America, mainly focusing on several features of responsible medicaments. Also, we highlighted the most critical points on the management of hepatotoxicity in general and those based on findings from our Latin American experience in particular.

Identification of the interferon-inducible GTPase GBP1 as major restriction factor for the Hepatitis E virus

This study aims to gain deeper insight into HEV-induced innate immunity by characterizing the crosstalk between the virus and the host factor guanylate-binding protein 1 (GBP1). We observe that the amount of GBP1 is elevated upon infection, although number of transcripts is decreased, which is explained by a prolonged protein half-life. Modulation of GBP1 levels via overexpression significantly inhibits the viral life cycle. Use of various GBP-1 mutants revealed that the antiviral effect of GBP-1 on HEV is independent from the GTPase-activity, but depends on the capacity of GBP-1 to form GBP1 homodimers. This connects GBP-1 to the autophagosomal pathway. Indeed, dimerization competent GBP1 targets the viral capsid protein to the lysosomal compartment leading to inactivation of the viral particle. Most importantly, silencing of GBP1 abolishes the antiviral effect of IFNγ on HEV. In IFNγ treated cells the virus is targeted to lysosomal structures and destroyed therein. This process depends in part on GBP1. These observations about the relevance of GBP1 for type II interferon-mediated innate immunity against HEV could be a base for tailoring novel antivirals and improvement of disease management.IMPORTANCE Although HEV represents a worldwide public health problem with 20 million infections and 44.000 death cases per year, there are still no specific antivirals available and many aspects of the viral life cycle are not well understood. Here we identify the guanylate binding protein 1 (GBP1) as a restriction factor affecting life cycle of HEV. Surprisingly, the antiviral effect of GBP1 does not depend on its GTPase function, but on its capacity to homodimerize. We revealed that GBP1 exerts its antiviral activity by targeting HEV to the lysosomal compartment where the virus is inactivated. Most importantly, we observed that the antiviral effect of interferon-γ on HEV strongly depends on GBP1. Our observation that GBP1 impairs HEV and is crucial for the antiviral effect of interferons on HEV extends understanding of host defense-mechanisms. As the interferon-system represents a universal defense-mechanism, our study could help to design novel antivirals targeting.

Targeting Cholesterol Metabolism as Efficient Antiviral Strategy Against the Hepatitis E Virus

BACKGROUND AND AIMS

The Hepatitis E virus hijacks the endosomal system for its release. These structures are highly dependent on cholesterol. Hence, this study investigates the impact of HEV on cholesterol-metabolism, the effect of intracellular cholesterol content on HEV-release and the potential of cholesterol-modulators to serve as antivirals.

METHODS

Intracellular cholesterol-content of cells was modulated and impacts on HEV were monitored using qPCR, Western blot, microscopy, virus-titration and density-gradient centrifugation. Blood-lipids and HEV-RNA were routinely quantified in chronically infected patients during follow-up visits.

RESULTS

In HEV-infected cells, decreased levels of cholesterol are found. In patients, HEV infection decreases serum-lipid concentrations. Importantly, statin treatment herein increases viral titers. Similarly, reduction of intracellular cholesterol via simvastatin treatment increases viral release in vitro. On the contrary, elevating intracellular cholesterol via LDL or 25-hydroxycholesterol strongly reduces viral release due to enhanced lysosomal degradation of HEV. Drug-induced elevation of intracellular cholesterol via fenofibrate or PSC833 impairs HEV release via the same mechanism.

CONCLUSIONS

This study analyses the crosstalk between HEV and intracellular cholesterol. The results highlight the importance of an intact cholesterol homeostasis for HEV-release and thereby identify a potential target for antiviral strategies. Especially fenofibrate is considered a promising novel antiviral against HEV. Beyond this, the study may help clinicians evaluating co-treatments of HEV-infected patients with statins, as this may be counter indicated.

Current Paradigm of Hepatitis E Virus Among Pediatric and Adult Patients

Hepatitis E virus (HEV) infection is a polymorphic condition, present throughout the world and involving children and adults. Multiple studies over the last decade have contributed to a better understanding of the natural evolution of this infection in various population groups, several reservoirs and transmission routes being identified. To date, acute or chronic HEV-induced hepatitis has in some cases remained underdiagnosed due to the lower accuracy of serological tests and due to the evolutionary possibility with extrahepatic manifestations. Implementation of diagnostic tests based on nucleic acid analysis has increased the detection rate of this disease. The epidemiological and clinical features of HEV hepatitis differ depending on the geographical areas studied. HEV infection is usually a self-limiting condition in immunocompetent patients, but in certain categories of vulnerable patients it can induce a sudden evolution toward acute liver failure (pregnant women) or chronicity (immunosuppressed patients, post-transplant, hematological, or malignant diseases). In acute HEV infections in most cases supportive treatment is sufficient. In patients who develop chronic hepatitis with HEV, dose reduction of immunosuppressive medication should be the first therapeutic step, especially in patients with transplant. In case of unfavorable response, the initiation of antiviral therapy is recommended. In this review, the authors summarized the essential published data related to the epidemiological, clinical, paraclinical, and therapeutic aspects of HEV infection in adult and pediatric patients.

Hepatitis E Virus Infection: Is It Really a Problem in Latin America?

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Seroprevalence of hepatitis E virus antibodies in different human populations of Cameroon

Hepatitis E virus (HEV) is a major cause of acute hepatitis worldwide. HEV infection is self-limiting, but fulminant hepatitis may occur with higher mortality rates. The aim of this study was to determine the seroprevalence of the HEV in three different populations in Cameroon and to assess alimentary risk factors of infection. A total of 903 individuals including 450 elderly people, 183 pregnant women, and 270 HIV-infected patients were enrolled during 2009-2015. All sera obtained were tested for the presence of anti-HEV antibodies with commercial enzyme-linked immunosorbent assay kits. The association between initial anti-HEV status and potential risk factors was assessed. Out of the 903 samples, 22.0% (199/903) were positives for anti-HEV immunoglobulin M (IgM), 5.8% (52/903) for anti-HEV IgG, and 3.5% (32/903) for both. The seropositivity for IgM was 7.0%, 13.1%, and 34.7%; meanwhile, the seropositivity for immunoglobulin G was 8.5%, 3.3%, and 5.1%, in HIV-infected patients, pregnant women, and the elderly population, respectively. Both antibodies were detected simultaneously in 2.2%, 1.6%, and 5.1% in HIV-infected patients, pregnant women, and the elderly population, respectively. No risk factors were significantly associated with HEV infection in these populations. This study showed a high prevalence of anti-HEV antibodies in three different populations in Cameroon.

Detection of hepatitis E virus antibodies among Cercopithecidae and Hominidae monkeys in Cameroon

We screened hepatitis E from 15 species of non-human primates. Anti-HEV IgG was detected in 11.1% (1/9) Mandrillus sphinx, 14.3% (2/14) Gorilla gorilla, 5.9% (4/67) pan troglodytes and 8.7% (2/23) Mandrillus leucophaeus, whereas anti-HEV IgM was detected in 1.5% (1/18) papio Anubis, 28.6% (2/7) Cercocebus agilis and 1.5% (1/67) pan troglodyte.

Meta-transcriptomic analysis reveals a new subtype of genotype 3 avian hepatitis E virus in chicken flocks with high mortality in Guangdong, China

Background

Hepatitis E virus (HEV) is one of most important zoonotic viruses, and it can infect a wide range of host species. Avian HEV has been identified as the aetiological agent of big liver and spleen disease or hepatitis-splenomegaly syndrome in chickens. HEV infection is common among chicken flocks in China, and there are currently no practical measures for preventing the spread of the disease. The predominant avian HEV genotype circulating in China have been identified as genotype 3 strains, although some novel genotypes have also been identified from chicken flocks in China.

Results

In this study, we used a meta-transcriptomics approach to identify a new subtype of genotype 3 avian HEV in broiler chickens at a poultry farm located in Shenzhen, Guangdong Province, China. The complete genome sequence of the avian HEV, designated CaHEV-GDSZ01, is 6655-nt long, including a 5′ UTR of 24 nt and a 3′ UTR of 125 nt (excluding the poly(A) tail), and contains three open reading frames (ORFs). Sequence analysis indicated that the complete ORF1 (4599 nt/1532 aa), ORF2 (1821 nt/606 aa) and ORF3 (264 nt/87 aa) of CaHEV-GDSZ01 share the highest nucleotide sequence identity (85.8, 86.7 and 95.8%, respectively) with the corresponding ORFs of genotype 3 avian HEV. Phylogenetic analyses further demonstrated that the avian HEV identified in this study is a new subtype of genotype 3 avian HEV.

Conclusions

Our results demonstrate that a new subtype of genotype 3 avian HEV is endemic in Guangdong, China, and could cause high mortality in infected chickens. This study also provides full genomic data for better understanding the evolutionary relationships of avian HEV circulating in China. Altogether, the results presented in this study suggest that more attention should be paid to avian HEV and its potential disease manifestation.

Serological and molecular retrospective analysis of hepatitis E suspected cases from the Eastern Brazilian Amazon 1993-2014

INTRODUCTION

We evaluated the anti-hepatitis E virus (HEV) antibody prevalence and HEV-RNA in archived serum samples of non-A-C hepatitis, or suspected cases of HEV infection from the Eastern Brazilian Amazon from 1993 to 2014.

METHODS

Serum samples (n = 318) were tested using ELISA and immunoblotting, and screened for HEV-RNA by RT-qPCR.

RESULTS

Anti-HEV IgM and IgG were detected in 3.4% (11/318) and 5.9% (19/318) of the samples, respectively. All samples were HEV-RNA negative.

CONCLUSIONS

HEV was detected at a low prevalence. Broader serological and molecular evaluation of HEV infection in the Amazon region should be carried out.

Transmission of hepatitis E virus by water: An issue still pending in industrialized countries

Hepatitis E virus (HEV) is an enteric virus divided into eight genotypes. Genotype 1 (G1) and G2 are specific to humans; G3, G4 and G7 are zoonotic genotypes infecting humans and animals. Transmission to humans through water has been demonstrated for G1 and G2, mainly in developing countries, but is only suspected for the zoonotic genotypes. Thus, the water-related HEV hazard may be due to human and animal faeces. The high HEV genetic variability allows considering the presence in wastewater of not only different genotypes, but also quasispecies adding even greater diversity. Moreover, recent studies have demonstrated that HEV particles may be either quasi-enveloped or non-enveloped, potentially implying differential viral behaviours in the environment. The presence of HEV has been demonstrated at the different stages of the water cycle all over the world, especially for HEV G3 in Europe and the USA. Concerning HEV survival in water, the virus does not have higher resistance to inactivating factors (heat, UV, chlorine, physical removal), compared to viral indicators (MS2 phage) or other highly resistant enteric viruses (Hepatitis A virus). But the studies did not take into account genetic (genogroups, quasispecies) or structural (quasi- or non-enveloped forms) HEV variability. Viral variability could indeed modify HEV persistence in water by influencing its interaction with the environment, its infectivity and its pathogenicity, and subsequently its transmission by water. The cell culture methods used to study HEV survival still have drawbacks (challenging virus cultivation, time consuming, lack of sensitivity). As explained in the present review, the issue of HEV transmission to humans through water is similar to that of other enteric viruses because of their similar or lower survival. HEV transmission to animals through water and how the virus variability affects its survival and transmission remain to be investigated.

Hepatitis E virus infection among rural Afro-descendant communities from the eastern Brazilian Amazon

INTRODUCTION

The prevalence, public health impact, and epidemiological characteristics of hepatitis E virus (HEV) are poorly understood in Brazil.

METHODS

Serum samples from 535 individuals from three rural Afro-descendant communities located in eastern Brazilian Amazon were collected in October 2015 and tested for presence of anti-HEV IgM and IgG antibodies. Serologically positive samples were also tested for HEV-RNA.

RESULTS

Two cases were confirmed for anti-HEV IgM (0.3 %) and two cases for anti-HEV IgG (0.3 %). No sample was positive for HEV-RNA.

CONCLUSIONS

Results indicated low prevalence of HEV infection in Afro-descendant rural communities from the eastern Brazilian Amazon.

Epidemiological investigation of the novel genotype avian hepatitis E virus and co-infected immunosuppressive viruses in farms with hepatic rupture haemorrhage syndrome, recently emerged in China

Since 2016, hepatic rupture haemorrhage syndrome (HRHS) appeared in chickens of China and caused huge economic loss. To assess the infection status of the avian hepatitis E virus (HEV) and co-infected viruses, including avian leukosis virus (ALV), reticuloendotheliosis virus (REV), fowl adenovirus (FAdV), and chicken infectious anaemia virus (CIAV), in farms with HRHS, 180 liver samples were collected from 24 farms in different provinces and detected by strict molecular virology methods. Results showed that the positive rates of HEV, ALV, REV, FAdV, and CIAV were 74.44%, 20.00%, 27.78%, 31.11%, and 12.22%, respectively, whereas there are also 112 samples with co-infection, for a rate of 58%. Meanwhile, the positive rate of HEV decreased gradually with age; the lowest positive rate of ALV (5.76%) and REV (19.23%) appeared in 25-35 weeks age, during which the positive rate of CIAV was the highest (19.23%); the positive rate of HEV in layers (64.00%) was lower than that of broilers (83.33%), but the positive rates of ALV (38.46%) and CIAV (15.38%) in layers were higher than that of broilers (5.88%, 9.80%); the positive rates of HEV (75.88%) and CIAV (15.60%) in parental generation (PG) were higher than that of commodity generation (CG, 64.10%, 0.00%), whereas the positive rate of ALV showed inverse relationship (PG: 14.89%; CG: 38.46%). Additionally, phylogenetic analysis showed that all the avian HEV identified this study belong to a novel genotype, and found the close relationship between the wild strains (REV and CIAV) and corresponding isolates from contaminated vaccine. The data presented in this report will enhance the current understanding of the epidemiology characteristics in farms with HRHS in China.

Hepatitis E virus is not detected in association with neurological disorders among Brazilian children

Hepatitis E virus is increasingly being associated with idiopathic neurological disease. We tested 325 stool samples from Brazilian children presenting acute flaccid paralysis or Guillain-Barré syndrome using a broadly reactive and sensitive Reverse-transcription Polymerase chain reaction. Hepatitis E genome was not detected in any of the samples tested. Our results suggest that hepatitis E virus does not seem to be associated as the etiologic agent of acute flaccid paralysis and Guillain-Barré syndrome cases occurred in Brazilian children during the period of investigation (2010-2012).

Hepatitis E virus: reasons for emergence in humans

Hepatitis E virus (HEV) infects both humans and other animal species. Recently, we have seen a steady increase in autochthonous cases of human HEV infection in certain areas especially in Europe, and large outbreaks in several African countries among the displaced population. This mini-review critically analyzes potential host, environmental, and viral factors that may be associated with the emergence of hepatitis E in humans. The existence of numerous HEV reservoir animals such as pig, deer and rabbit results in human exposure to infected animals via direct contact or through animal meat consumption. Contamination of drinking, irrigation and coastal water by animal and human wastes lead to emergence of endemic cases in industrialized countries and outbreaks in displaced communities especially in war-torn countries.

Hepatitis E seroprevalence in the Americas: A systematic review and meta-analysis

BACKGROUND & AIMS

While hepatitis E virus infections are a relevant topic in Europe, knowledge about epidemiology of hepatitis E virus infections in the USA and Latin America is still limited. Aim of this study was to estimate anti-hepatitis E virus IgG seroprevalence in the Americas and to assess whether low socioeconomic status is associated with hepatitis E virus exposure.

METHODS

We performed a systematic review and meta-analysis. Literature search was performed in PubMed for articles published 01/1994-12/2016. Prevalence was estimated using a mixed-effects model and reported in line with PRISMA reporting guidelines.

RESULTS

Seroprevalence was significantly higher in the USA than in Latin America, independently of assay, patient cohort, methodological quality or study year (OR: 1.82 (1.06-3.08), P = .03). Patients in the USA had a more than doubled estimated seroprevalence (up to 9%, confidence interval 5%-15.6%) than those in Brazil (up to 4.2%, confidence interval 2.4%-7.1%; OR: 2.27 (1.25-4.13); P = .007) and Mixed Caribbean (up to 1%, OR: 8.33 (1.15-81.61); P = .04). A comparison with published data from Europe demonstrated that anti-hepatitis E virus seroprevalence in the USA and Europe did not differ significantly (OR: 1.33 (0.81-2.19), P = .25), while rate in South America was significantly lower than that in Europe (OR: 0.67 (0.45-0.98), P = .04).

CONCLUSIONS

Hepatitis E virus is common in the USA. Surprisingly, the risk of hepatitis E virus exposure was low in many South American countries. Seroprevalence did not differ significantly between Europe and the USA. Hence, hepatitis E virus is not limited to countries with low sanitary standards, and a higher socioeconomic status does not protect populations from hepatitis E virus exposure.

Evidence of hepatitis E virus infections among persons who use crack cocaine from the Midwest region of Brazil

The current study aimed to determine the seroprevalence of hepatitis E virus (HEV) infection among persons who use crack from Midwest region of Brazil. Sera samples from 698 users of crack, collected from November 2013 to July 2015 were tested for anti-HEV immunoglobulin G (IgG) and immunoglobulin M (IgM) markers. Of the 698 serum samples, 99 (14.2%) were positive for anti-HEV IgG. Two samples were positive for anti-HEV IgM but both were negative for HEV RNA. The variables independently associated with anti-HEV positivity were increasing age and absence of stable partnership. This study showed high prevalence of past hepatitis E virus infection among persons who use crack.

Characterization of the novel genotype avian hepatitis E viruses from outbreaks of hepatic rupture haemorrhage syndrome in different geographical regions of China

Since 2016, hepatic rupture haemorrhage syndrome (HRHS) has emerged in layer and broiler breeder hens in several provinces of China, and novel genotype avian hepatitis E viruses were detected from these chickens. To gain a better understanding of the genetic properties of the novel avian HEV strain, the capsid gene of four isolates from birds at four farms experiencing HRHS in different geographical regions were determined and compared with those of reported pathogenic and nonpathogenic avian HEV isolates as well as mammalian HEVs. Results showed that all those isolates share 80.1%-88.2% nucleotide sequence identity and 89.3%-91.9% amino acid sequence identity with other published avian HEV strains, while phylogenetic analysis further demonstrate that a novel genotype avian HEV was epidemic in China. Meanwhile, sequence analysis revealed that those novel isolates contain various amino acid mutations and even a hypervariable region in their major antigenic domains, which might be the critical factors for the pathogenicity elevation and even change their antigenicity. The data presented in this report will enhance the current understanding of the epidemiology and genetic diversity of the novel genotype avian HEV in China and provide additional insight into the critical factors that determine the pathogenicity of it.

Phylogenetic Analysis and Characterization of the Complete Hepatitis E Virus Genome (Zoonotic Genotype 3) in Swine Samples from Mexico

Hepatitis E virus (HEV) is an emerging public health problem with an estimated 20 million infections each year. In Mexico, Orthohepevirus A, genotype 2, has been reported in humans, but genotype 3 has only been reported in swine (zoonotic). No diagnostic tests are publicly available in Mexico, and only partial sequences have been reported from swine samples. Hence, research is necessary to determine circulating strains, understand the features and dynamics of infection on pig farms, determine how to implement surveillance programs, and to assess public health risks. In this study, a next-generation sequencing (NGS) approach was applied to obtain a complete genome of swine HEV. Liver, feces, and bile samples were taken at slaughterhouses and a farm in Mexico. RT-PCR was used to determine positive samples and confirmed by Sanger sequencing. Of the 64 slaughterhouse samples, one bile sample was positive (B1r) (1.56%). Of 21 sample pools from farm animals, 14 were positive (66.66%), representing all stages of production. A complete sequence strain MXCDg3_B1c|_2016 was obtained from the bile of a domestic swine in the fattening stage. In addition, two partial sequences—MXCDg3_H2cons|_2016 (1473 nt) and MXCDg3_C3Acons|_2016 (4777 nt)—were obtained from sampled farm animals. Comparison with all reported genome HEV sequences showed similarity to genotype 3 subgenotype a (G3a), which has been previously reported in acute cases of human hepatitis in the US, Colombia, China, and Japan.

Inhibition of Hepatitis E Virus Spread by the Natural Compound Silvestrol

Every year, there are about 20 Mio hepatitis E virus (HEV) infections and 60,000 deaths that are associated with HEV worldwide. At the present, there exists no specific therapy for HEV. The natural compound silvestrol has a potent antiviral effect against the (-)-strand RNA-virus Ebola virus, and also against the (+)-strand RNA viruses Corona-, Picorna-, and Zika virus. The inhibitory effect on virus spread is due to an inhibition of the DEAD-box RNA helicase eIF4A, which is required to unwind structured 5'-untranslated regions (UTRs). This leads to an impaired translation of viral RNA. The HEV (+)-strand RNA genome contains a 5'-capped, short 5'-UTR. This study aims to analyze the impact of silvestrol on the HEV life cycle. Persistently infected A549 cells were instrumental. This study identifies silvestrol as a potent inhibitor of the release of HEV infectious viral particles. This goes along with a strongly reduced HEV capsid protein translation, retention of viral RNA inside the cytoplasm, and without major cytotoxic effects. Interestingly, in parallel silvestrol affects the activity of the antiviral major vault protein (MVP) by translocation from the cytoplasm to the perinuclear membrane. These data further characterize the complex antiviral activity of silvestrol and show silvestrol's broad spectrum of function, since HEV is a virus without complex secondary structures in its genome, but it is still affected.

Challenges in research and management of hepatitis E virus infection in Cuba, Mexico, and Uruguay

The symposium "Epidemiology of Hepatitis E virus (HEV) Infection and Associated Immune Response" was held at the Universidad de Guadalajara, Mexico, on 14 June 2017, to define the status of research on HEV infection in three countries in Latin America and the Caribbean (LAC)-Cuba, Mexico, and Uruguay-compared to the situation in Germany. Scientists identified specific research gaps in understanding HEV transmission and the resulting impact on development of disease in the three abovementioned LAC countries. Specific recommendations for implementing standardized serologic and molecular diagnostic methods and epidemiologic, basic, and applied research aimed to develop prevention and handling strategies for this infection, along with the associated comorbidities in the three LAC countries, were also discussed. Given similar demographic, sanitary, and economic conditions in other LAC countries that could predispose them to be at high risk for HEV transmission and infection, these research gaps and recommendations might apply to the entire LAC region. This report was -prepared by meeting participants based on 1) symposium presentations, 2) literature reviews, and 3) group discussions.

Seroprevalence of Hepatitis A Virus, Hepatitis E Virus, and Helicobacter pylori in Rural Communities of the Bolivian Chaco, 2013

In the Bolivian Chaco, south-east of Bolivia, studies conducted over the past three decades reported hepatitis A virus (HAV) and Helicobacter pylori seroprevalences above 90% and 60%, respectively. Hepatitis E virus (HEV) prevalence was previously found to be 6-7% but is probably an underestimate because of the poor sensitivity of the assays used. In November 2013, we conducted a cross-sectional study of 263 healthy volunteers from two rural communities of the Bolivian Chaco, aiming to reassess HAV, HEV, and H. pylori seroprevalence 10-20 years following the previous surveys. Hepatitis A virus seroprevalence was 95%, with universal exposure after the first decade of life; HEV seroprevalence was considerably higher (31-35%) than that previously reported; H. pylori seroprevalence was 59%, with an age-dependent distribution. The high prevalence of these infections suggests that major efforts are still needed to reduce fecal-oral transmission and to improve human health in the Bolivian Chaco.

Seroprevalence of hepatitis E virus in chronic hepatitis C in Brazil

BACKGROUND AND AIMS

Hepatitis E virus infection in patients with underlying chronic liver disease is associated with liver decompensation and increased lethality. The seroprevalence of hepatitis E virus in patients with chronic hepatitis C in Brazil is unknown. This study aims to estimate the seroprevalence of hepatitis E virus in patients with chronic hepatitis C and to describe associated risk factors.

METHODS

A total of 618 patients chronically infected with hepatitis C virus from three reference centers of São Paulo, Brazil were included. Presence of anti-HEV IgG was assessed by enzyme-linked immunosorbent assay (WANTAI HEV-IgG ELISA).

RESULTS

Out of the 618 patients tested, 10.2% turned out positive for anti-HEV IgG (95% CI 8.0-12.8%). Higher seroprevalence was found independently associated with age over 60 years (OR=2.04; p=0.02) and previous contact with pigs (OR=1.99; p=0.03).

CONCLUSIONS

Patients with chronic hepatitis C are under risk of hepatitis E virus superinfection in São Paulo. Contact with pigs is a risk factor for the infection, suggesting a possible zoonosis with oral transmission.

Origin and dispersal of Hepatitis E virus

Hepatitis E virus (HEV, genus Orthohepevirus) is a common cause of hepatitis worldwide. Human-infecting HEV strains (Orthohepevirus A) include human-restricted and enzootic genotypes. Viruses in the Orthohepevirus A species also infect rabbits (HEV-3ra), camels, and swine. Using a selection-informed method, we dated the origin of the Orthohepevirus genus at least 21 million years ago, whereas the Orthohepevirus A species originated in Asia, most likely from a human-infecting ancestor that existed ~4500 to 6800 years ago. In this period, the appearance of large human settlements probably facilitated HEV emergence and spread. The earliest events in Orthohepevirus A evolutionary history involved the separation of the enzootic and human-restricted genotypes, as well as the split of the camel-infecting genotypes, which occurred during the time-frame of camel domestication. The place and timing of HEV-3ra divergence also correspond to the circumstances of rabbit domestication. This study clarifies the origin and historical events underlying HEV dispersal.

A Cross-Sectional Study of Viral Hepatitis Perception among Residents from Southeast and North Regions of Brazil

Few data are available regarding viral hepatitis perception among the general global population. The present study aims to estimate the perception of viral hepatitis in a cohort of individuals living in two geographical regions of Brazil: North (Manaus city (MA)) and Southeast (Rio de Janeiro city (RJ)). A cross-sectional, descriptive study was carried out among 287 subjects recruited in MA (134) and RJ (153). All individuals answered a questionnaire assessing socio-demographic characteristics and viral hepatitis awareness. Participants’ responses were scored and divided using interquartile values. Associations between socio-demographic characteristics and knowledge were also evaluated. Interquartile analysis scored 0–21 correct answers as “Very Weak”; 22–27 as “Weak”; 28–31 as “Intermediate”; and 32–47 as “Desirable”. Mean ± standard deviations (SD) of correct responses were weak in both MA (24.1 ± 7.0) and RJ (26.3 ± 7.3). Bivariate analysis showed an association between viral hepatitis awareness and both education level (p < 0.001) and family income (p < 0.01). Desirable scores were more common in female participants (61%), those aged between 21–30 years (40%), those with a secondary education (51.7%), those who received high income (31.6%), and those from RJ (70.0%). Health education campaigns in these cities are recommended to increase knowledge and reduce the transmission of these viruses.

Epidemiology of Hepatitis E

Hepatitis E virus (HEV) is globally prevalent with relatively high percentages of anti-HEV immunoglobulin G-positive individuals in the populations of developing and developed countries. There are two distinct epidemiologic patterns of hepatitis E. In areas with high disease endemicity, primarily developing countries in Asia and Africa, this disease is caused mainly by genotype 1 or 2 HEV, both of which transmit predominantly through contaminated water and occur as either outbreaks or as sporadic cases of acute hepatitis. The acute hepatitis caused by either of these two genotypes has the highest attack rate in young adults, and the disease is particularly severe among pregnant women. In developed countries, sporadic cases of locally acquired genotype 3 or 4 HEV infection are observed. The reservoir of genotype 3 and 4 HEV is believed to be animals, such as pigs, with zoonotic transmission to humans. The affected persons are often elderly, and persistent infection has been well documented among immunosuppressed persons. A subunit vaccine has been shown to be effective in preventing clinical disease and has been licensed in China.

First evidence of the Hepatitis E virus in environmental waters in Colombia

Hepatitis E virus (HEV) is one of the main causes of acute viral hepatitis of enteric transmission. HEV has been detected in environmental samples in several countries from Europe and Asia, constituting a risk factor for waterborne infection. In Colombia, HEV has been identified in samples obtained from patients as well as from swine, but no environmental studies have been carried out. To determine if HEV is present in environmental waters, samples from the main source of drinking water plant and of wastewater system of eight municipalities and two villages of Antioquia state (North West Colombia), were collected between December 2012 and April 2014. The HEV genome was detected by RT-PCR in 23.3% (7/30) of the samples from the main source of drinking water plants and in 16.7% (5/30) from sewage. Viral concentrates obtained from three positive sewage samples were used to inoculate HepG2 cell cultures that were followed for one month; however, the viral genome was not detected in any cell culture. This study demonstrates the circulation of HEV in both source of drinking water plants and wastewater in Antioquia state, Colombia. The presence of HEV in environmental waters could be a risk for waterborne transmission in this population. The findings of the present study, together with the evidence of HEV circulation in human and swine in Colombia, should be consider by public health authorities for the development of surveillance programs and the inclusion of HEV infection diagnosis in the guidelines of viral hepatitis in the country. This is the first report of HEV in environmental samples in Colombia and the second one in Latin America.

In house ELISA based on recombinant ORF2 protein underline high prevalence of IgG anti-hepatitis E virus amongst blood donors in south Brazil

Hepatitis E Virus (HEV) is a zoonotic pathogen responsible for causing acute hepatitis in human, especially in developing countries. Diagnosis of HEV usually relies on the detection of antibodies mostly by enzyme-linked immunosorbent assay (ELISA). In the present study, we designed a new indirect ELISA (iELISA) based on a short recombinant peptide derived from the capsid protein (ORF2p) and demonstrated its potential for detecting human IgG against HEV genotype 3. The best polystyrene plate (Maxisorp^®), optimal ORF2p coating antigen concentration (0,67μg/well) and primary antibody dilution (1:100) were determined. This iELISA showed a sensitivity of 91.4% and specificity of 95.9%. The comparison of our in house iELISA with a commercial assay (RecomWell, Mikrogen^®) showed 94.25% of agreement and a kappa index of 0.88. The ORF2 recombinant ELISA was used to screen 780 blood donors for anti-HEV IgG and we found that 314 (40,25%) of these donors were IgG positive. This high prevalence of antibodies suggests, for the first time, that the Southern Brazil region might be endemic to Hepatitis E Virus genotype 3.

High frequency of hepatitis E virus infection in swine from South Brazil and close similarity to human HEV isolates

Hepatitis E virus is responsible for acute and chronic liver infections worldwide. Swine hepatitis E virus has been isolated in Brazil, and a probable zoonotic transmission has been described, although data are still scarce. The aim of this study was to investigate the frequency of hepatitis E virus infection in pigs from a small-scale farm in the rural area of Paraná State, South Brazil. Fecal samples were collected from 170 pigs and screened for hepatitis E virus RNA using a duplex real-time RT-PCR targeting a highly conserved 70nt long sequence within overlapping parts of ORF2 and ORF3 as well as a 113nt sequence of ORF2. Positive samples with high viral loads were subjected to direct sequencing and phylogenetic analysis. hepatitis E virus RNA was detected in 34 (20.0%) of the 170 pigs following positive results in at least one set of screening real-time RT-PCR primers and probes. The swine hepatitis E virus strains clustered with the genotype hepatitis E virus-3b reference sequences in the phylogenetic analysis and showed close similarity to human hepatitis E virus isolates previously reported in Brazil.

New insights into the hepatitis E virus genotype 3 phylodynamics and evolutionary history

Hepatitis E virus (HEV) is an emergent hepatotropic virus endemic mainly in Asia and other developing areas. However, in the last decade it has been increasingly reported in high-income countries. Human infecting HEV strains are currently classified into four genotypes (1-4). Genotype 3 (HEV-3) is the prevalent virus genotype and the mostly associated with autochthonous and sporadic cases of HEV in developed areas. The evolutionary history of HEV worldwide remains largely unknown. In this study we reconstructed the spatiotemporal and population dynamics of HEV-3 at global scale, but with particular emphasis in South America, where case reports have increased dramatically in the last years. To achieve this, we applied a Bayesian coalescent-based approach to a comprehensive data set comprising 97 GenBank HEV-3 sequences for which the location and sampling date was documented. Our phylogenetic analyses suggest that the worldwide genetic diversity of HEV-3 can be grouped into two main Clades (I and II) with a Ƭmrca dated in approximately 320years ago (95% HPD: 420-236years) and that a unique independent introduction of HEV-3 seems to have occurred in Uruguay, where most of the human HEV cases in South America have been described. The phylodynamic inference indicates that the population size of this virus suffered substantial temporal variations after the second half of the 20th century. In this sense and conversely to what is postulated to date, we suggest that the worldwide effective population size of HEV-3 is not decreasing and that frequently sources of error in its estimates stem from assumptions that the analyzed sequences are derived from a single panmictic population. Novel insights on the global population dynamics of HEV are given. Additionally, this work constitutes an attempt to further describe in a Bayesian coalescent framework, the phylodynamics and evolutionary history of HEV-3 in the South American region.

Prevalence of Hepatitis E Virus (HEV) Antibodies in Mexican Pigs

The hepatitis E virus (HEV) is the causative agent of Hepatitis E, an enterically transmitted disease. HEV infections in pigs and humans have been reported worldwide, but data from Mexico are scarce. In the present study, the prevalence of anti-HEV IgG antibodies was investigated in a quite large number of swine from Mexico by means of an ELISA based on a recombinant open reading frame 2 protein of HEV genotype 3. Serum samples from 683 healthy pigs (1-48 months old), collected during 2010-2013 in 109 herds from 48 municipalities located in 9 states in the centre of the country were assayed. A 30.75 % (210/683) of the sera tested were positive, and they were distributed along all the states included in the study. The prevalence of anti-HEV antibodies varied widely between municipalities and herds, and it was higher in pigs 4-6 months of age. No relationships were detected between seroprevalences and farm characteristics. Forty individual faecal samples were analysed by RT-PCR and all resulted negative. These data indicate that HEV infection is widespread in Mexican pigs; thus, representing a potential zoonotic risk for humans.

Hepatitis E virus infection in the HIV-positive patient

Hepatitis E virus (HEV) is a RNA virus that can cause hepatitis. In immunocompetent individuals, infection with HEV usually leads to asymptomatic seroconversion. However, in immunosuppressed patients, such as transplant recipients, HEV can develop into a chronic infection. Studies regarding the seroprevalence and clinical implications of HEV in patients infected with the human immunodeficiency virus (HIV) are conflicting. Levels of CD4 count in blood seem to be the most widely associated risk factor, while other factors such as meat consumption or proximity to animals are less clearly associated with HEV infection. Progression to chronicity, as well as extrahepatic manifestations of HEV seem rare in HIV, and the implications of HEV in liver disease progression are poorly understood in the HIV-infected. In this review we describe the epidemiology, risk factors, and clinical implications of HEV infection in individuals infected with HIV.

Hepatitis E virus seroprevalence among schistosomiasis patients in Northeastern Brazil

Background

Hepatitis E virus (HEV) can cause chronic infection with rapid progression to liver cirrhosis in immunocompromised patients. HEV seroprevalence in patients with Schistosoma mansoni in Brazil is unknown. We evaluated the prevalence of past or present HEV infection in schistosomiasis patients in Recife, Pernambuco, Brazil. A total of 80 patients with Schistosoma mansoni were consecutively enrolled in a cross-sectional study. Serum samples were tested for the presence of anti-HEV IgG antibodies by enzyme immunoassay (Wantai anti-HEV IgG, Beijing, China) and for the presence of HEV RNA using real time reverse transcriptase-polymerase chain reaction with primers targeting the HEV ORF2 and ORF3. Clinical and laboratory tests as well as abdominal ultrasound were performed at the same day of blood collection.

Results

Anti-HEV IgG was positive in 18.8% (15/80) of patients with SM. None of the samples tested positive for anti-HEV IgM or HEV-RNA. Patients with anti-HEV IgG positive presented higher levels of alanine aminotranferase (p = 0.048) and gama-glutamil transferase (p = 0.022) when compared to patients without anti-HEV IgG antibodies.

Conclusion

This study demonstrates that the seroprevalence of HEV is high in patients with Schistosoma mansoni in Northeastern of Brazil. Past HEV infection is associated with higher frequency of liver enzymes abnormalities. HEV infection and its role on the severity of liver disease should be further investigated among patients with Schistosoma mansoni.

The Latin American DILI Registry Experience: A Successful Ongoing Collaborative Strategic Initiative

Drug induced liver injury (DILI) is a rare but well recognized serious adverse reaction. Pre-marketing studies may not detect liver injury, and DILI becomes very often apparent after the drug is launched to the market. Specific biomarkers for DILI prediction or diagnosis are not available. Toxic liver reactions present with a wide spectrum of phenotypes and severity, and our knowledge on the mechanisms underlying idiosyncratic reactions and individual susceptibility is still limited. To overcome these limitations, country-based registries and multicenter research networks have been created in Europe and North America. Reliable epidemiological data on DILI in Latin America (LA), a region with a large variety of ethnic groups, were however lacking. Fortunately, a LA network of DILI was set up in 2011, with the support of the Spanish DILI Registry from the University of Malaga. The primary aim of the Latin DILI Network (LATINDILIN) Registry was to prospectively identify bona fide DILI cases and to collect biological samples to study genetic biomarkers. Physicians involved in the project must complete a structured report form describing the DILI case presentation and follow-up which is submitted to a Coordinator Center in each country, where it is further assessed for completeness. During the last four years, several LA countries (Argentina, Uruguay, Chile, Mexico, Paraguay, Brazil, Ecuador, Peru, Venezuela and Colombia) have joined the network and committed with this project. At that point, to identify both our strengths and weaknesses was a very important issue. In this review, we will describe how the LATINDILI Registry was created. The aims and methods to achieve these objectives will be discussed in depth. Additionally, both the difficulties we have faced and the strategies to solve them will be also pinpointed. Finally, we will report on our preliminary results, and discuss ideas to expand and to keep running this network.

Hepatitis E virus: An ancient hidden enemy in Latin America

Hepatitis E virus (HEV) infection is a common cause of acute clinical hepatitis worldwide. HEV is an RNA-containing virus and the only member of the genus Hepevirus in the family Hepeviridae. Human HEV is classified into four genotypes widely distributed across the world. The virus is mainly transmitted via the fecal-oral route, and water-borne epidemics have become characteristic of hepatitis E in developing countries, including those in Latin America. The zoonotic potential of HEV is broadly recognized. Thus, there is an urgent need to re-evaluate virus transmission scenarios and to enforce epidemiological surveillance systems. Additionally, it is known that HEV infections, initially defined as self-limiting, can also take chronic courses in immunocompromised patients. Moreover, we recently reported a high seroprevalence of HEV in samples from cirrhotic patients with no other etiological agents present, suggesting the potential role of HEV in the development of chronic liver illness. In this review, HEV genomic variability, transmission, chronic infectious course, zoonotic potential and treatment are discussed. Focus is placed on the impact of HEV infection in Latin America, to support the development of specific control strategies and the handling of this important and typically imperceptible viral infection.

Hepatitis E Virus Genotype 3 in Colombia: Survey in Patients with Clinical Diagnosis of Viral Hepatitis

Background

Hepatitis E virus is a major cause of outbreaks as well as sporadic hepatitis cases worldwide. The epidemiology of this enterically transmitted infection differs between developing and developed countries. The aims of this study were to describe HEV infection in Colombian patients and to characterize the genotype.

Methods

A prospective study was carried out on 40 patients aged over 15 with a clinical diagnosis of viral hepatitis, recruited from five primary health units in the city of Medellin, Colombia. Fecal samples obtained from the 40 consecutives cases were analyzed for HEV RNA using nested reverse transcription PCR for both ORF1 and ORF2-3. The amplicons were sequenced for phylogenetic analyses.

Results

Nine (22.5%) cases of HEV infection were identified in the study population. Three HEV strains obtained from patients were classified as genotype 3. No significant association was found between cases of Hepatitis E and the variables water drinking source, garbage collection system and contact with pigs.

Conclusions

This is the first prospective study of hepatitis E in Colombian patients. The circulation of the genotype 3 in this population is predictable considering the reports of the region and the identification of this genotype from pigs in the state of Antioquia, of which Medellin is the capital. Further studies are necessary to establish whether zoonotic transmission of HEV is important in Colombia.

Coinfection of hepatitis E virus and other hepatitis virus in Colombia and its genotypic characterization

INTRODUCTION

Hepatitis E virus has emerged as a public health problem, particularly in developing countries. The four genotypes identified in mammals include the G3 found in indigenous hepatitis in countries and regions with high porcine population, and the G1, associated with maternal deaths. 

OBJECTIVE

To determine coinfection by hepatitis E virus and the circulating genotypes in Colombia in 1,097 samples using serological markers for hepatitis A, B and C. 

MATERIALS AND METHODS

Serum samples of 1,097 patients from different regions of Colombia stored at the Laboratorio de Virología of the Instituto Nacional de Salud were selected to detect IgG and IgM anti-hepatitis E virus antibodies. The viral genomes of positive samples were amplified by RT-PCR, and the products were sequenced and phylogenetically analyzed by comparing ORF2 sequences deposited in the GenBank. 

RESULTS

IgG anti-hepatitis E virus antibodies were found in 278 samples, IgM in 62, and both markers in 64. Hepatitis E virus and hepatitis A virus coinfection determined by IgG anti-hepatitis E virus was 33.6% and 16.1% by IgM; hepatitis E virus and hepatitis B virus coinfection was 23.4% and 8.1%, and hepatitis E virus and hepatitis C virus coinfection was 35.4% and 5.83%, respectively. Among the 52 positive samples by PCR nine were sequenced and grouped within genotype 3A of the American porcine strain. 

CONCLUSIONS

The highest seropositivity was observed for hepatitis A and E. The incidence of hepatitis E virus coinfection with other hepatotropic viruses indicated that this pathogen is more frequent than expected. The circulation of genotype 3A implies that this disease may occur in outbreaks and as zoonosis in Colombia.

Epidemiology of hepatitis E virus infection during pregnancy in Benin

OBJECTIVES

Hepatitis E virus (HEV) is the cause of enterically transmitted non-A, non-C hepatitis (an infection that is particularly severe during pregnancy) in tropical and subtropical countries. As there are no published data concerning the prevalence of HEV antibodies in Benin, their presence was investigated in pregnant women undergoing routine HIV screening in a rural area in northern Benin and in pregnant women with acute non-A, non-C hepatitis.

METHODS

A total of 278 serum samples were collected from asymptomatic pregnant women in 2011 were tested for HEV and hepatitis A virus (HAV) antibodies, and the HEV IgM-positive samples were further tested for HEV-RNA. A further seven samples of pregnant women with acute non-A, non-C hepatitis collected during episodes of acute hepatitis in 2005 were also analysed.

RESULTS

Of the 278 samples collected in 2011, 16.19% were positive for HEV IgG and 1.44% for HEV IgM (none positive for HEV-RNA), and 99.64% were positive for total HAV antibodies (none positive for HAV IgM). Six of the seven samples collected in 2005 were positive for HEV IgG and IgM, and two were also positive for HEV-RNA.

CONCLUSIONS

The circulation of HEV infection is significant among pregnant women in Benin, in whom the consequences may be fatal.