Hepatitis E virus infection in Brazil: results of laboratory-based surveillance from 1998 to 2013

Hepatitis E virus infection increases the risk of diabetes and severity of liver disease in patients with chronic hepatitis C virus infection

OBJECTIVES

Co-infection with hepatitis A or B viruses may aggravate liver injury in patients infected with hepatitis C virus (HCV). However, few studies have assessed co-infection with hepatitis E virus (HEV) and HCV. Therefore, this study aimed to assess the prevalence and impact of HEV infection among Brazilian patients with chronic HCV infection.

METHODS

This observational study included adult patients with chronic HCV infection who were naive to antiviral therapy from January 2013 to March 2016. A total of 181 patients were enrolled, and HEV serology and PCR were performed for all patients.

RESULTS

Seropositivity for anti-HEV IgG was detected in 22 (12.0%) patients and anti-HEV immunoglobulin M in 3 (1.6%). HEV RNA showed inconclusive results in nine (4.9%) patients and was undetectable in the remaining patients. HEV serology positive patients had more severe liver disease, characterized by liver fibrosis ≥3 versus ≤2 (p<0.001), Aspartate Aminotransferase-to-Platelet Ratio Index of ≥1.45 (p=0.003), and Fibrosis-4 score of ≥3.25 (p=0.001). Additionally, the odds of HEV-positive patients developing diabetes mellitus were 3.65 (95% CI 1.40-9.52) times the corresponding odds of HEV-negative patients. A case-control-based histological analysis (n=11 HEV-HCV-positive patients and n=22 HCV-positive patients) showed no significant differences between the groups.

CONCLUSIONS

This prevalence is higher than that reported in previous studies of the general population in Brazil. Thus, HEV infection may influence the severity of liver disease and may represent an additional risk of developing diabetes mellitus in patients with HCV infection.

Systematic Review of Hepatitis E Virus in Brazil: A One-Health Approach of the Human-Animal-Environment Triad

Simple Summary

Hepatitis E virus (HEV) is an important causative agent of acute and chronic hepatitis worldwide. Originally identified in epidemics associated with flooding in Asia, it nowadays shows very distinct genetic and epidemiological patterns. While HEV genotypes (HEV-) 1 and 2 are associated with the original outbreaks (waterborne diseases), HEV-3 and HEV-4 present a zoonotic pattern (associated with consumption of meat from infected animals), HEV-5 and 6 have been found only in wild boar in Japan, and HEV-7 and 8 have been detected in camels and dromedary seldom affecting humans. Brazil, with a precarious sanitary structure and being an important world meat producer, was the focus of this study in order to identify patterns of occurrence of HEV. After reviewing scientific studies, it was identified that the only genotype found in Brazil is HEV-3 and the area where there were more reports was the South region of the country. This is the region that produces more pork. These results indicate that HEV-3 is widespread in the country and sanitary surveillance is essential in the national production of pigs, as well as the implementation of monitoring protocols in hospitals.

Abstract

Brazil is the fifth largest country in the world with diverse socioeconomic and sanitary conditions, also being the fourth largest pig producer in the world. The aim of the present systematic review was to collect and summarize all HEV published data from Brazil (from 1995 to October 2020) performed in humans, animals, and the environment, in a One Health perspective. A total of 2173 papers were retrieved from five search databases (LILACs, Mendeley, PubMed, Scopus, and Web of Science) resulting in 71 eligible papers after application of exclusion/inclusion criteria. Data shows that HEV genotype 3 (HEV-3) was the only retrieved genotype in humans, animals, and environment in Brazil. The South region showed the highest human seroprevalence and also the highest pig density and industry, suggesting a zoonotic link. HEV-1 and 2 were not detected in Brazil, despite the low sanitary conditions of some regions. From the present review we infer that HEV epidemiology in Brazil is similar to that of industrialized countries (only HEV-3, swine reservoirs, no waterborne transmission, no association with low sanitary conditions). Hence, we alert for the implementation of HEV surveillance systems in swine and for the consideration of HEV in the diagnostic routine of acute and chronic hepatitis in humans.

Seroprevalence of hepatitis E virus in risk populations and blood donors in a referral hospital in the south of Brazil

The prevalence of anti-hepatitis E virus (HEV) antibodies has a high heterogeneity worldwide. South American data are still scarce. The aim of this study was to evaluate the prevalence of HEV in populations at risk in comparison to blood donors (BD). A cross-sectional study was carried out in adults of different risk populations including crack users (CK), residents in a low income area (LIA), cirrhotic (CIR) and liver transplant patients (LT) compared with BD. The WANTAI HEV ELISA test was used and real-time PCR (in-house for screening and ALTONA as confirmatory test) for HEV RNA screening. A total of 400 participants were included. Anti-HEV IgG was positive in 19.5% of the total sample, reaching the highest rate in the CIR group, 22.5%, followed by CK, LT, and LIA (20%, 18.7%, and 17.5%, respectively). The prevalence found in BD individuals was of 18.7% (p = NS). Anti-HEV IgM was positive in only 1.5% of the sample (6/400). No blood or stools samples were positive for HEV RNA. The seroprevalence reported is among the highest rates ever found in Brazil. Considering the intense diagnostic investigation, data show that HEV circulation is more common that might be expected in our country.

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.

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.

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.

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.

Hepatitis E virus in South America: The current scenario

Hepatitis E virus (HEV) is one of the most frequent causes of acute viral hepatitis of enteric transmission worldwide. In South America the overall epidemiology has been little studied, and the burden of the disease remains largely unknown. A research of all scientific articles about HEV circulation in South America until November 2017 was carried out. Human seroprevalences of HEV varied according to the studied population: blood donors presented prevalence rates ranging from 1.8% to 9.8%, while reports from HIV-infected individuals, transplant recipients and patients on hemodialysis showed higher prevalence rates. Only 2 cases of chronic hepatitis in solid-organ transplant patients from Argentina and Brazil have been described. Detection of HEV in the swine population is widely prevalent in the region. Anti-HEV antibodies have also been recently documented in wild boars from Uruguay. Although scarce, studies focused on environmental and food HEV detection have shown viral presence in these kind of samples, highlighting possible transmission sources of HEV in the continent. HEV genotype 3 was the most frequently detected in the region, with HEV genotype 1 detected only in Venezuela and Uruguay. HEV is widely distributed throughout South America, producing sporadic cases of acute hepatitis, but as a possible agent of chronic hepatitis. Finding the virus in humans, animals, environmental samples and food, show that it can be transmitted through many sources, alerting local governments and health systems to improve diagnosis and for the implementation of preventive measures.

Detection and quantification of hepatitis E virus in the absence of IgG and IgM anti-HEV in HIV-positive patients

AIMS

To improve RT-qPCR with an internal control and a synthetic standard curve to detect HEV in HIV co-infected patients.

METHODS AND RESULTS

A single-stranded RNA (ssRNA) and a double-stranded DNA (dsDNA) synthetic curve were designed, compared to the international reference panel for HEV genotypes, and tested to quantify and detect a reference panel for HEV genotypes. The detection limit of the RNA synthetic curve (50 copies per ml) was better than the DNA synthetic curve (100 copies per ml) and the WHO standard curve (250 copies per ml). Then, 280 serum samples from HIV-positive patients were tested for HEV RNA, which was detected in 3·6% of serum samples. The viral load ranged from 2 × 10² copies per ml to 4·78 × 10⁸ copies per ml. HEV IgM/IgG antibodies were not detected in the RNA-positive patients. Sequencing analysis of HEV showed that the virus belongs to genotype 3 (HEV GT3).

CONCLUSIONS

Real-time PCR was a useful tool to estimate co-infection with HEV/HIV, even in patients with low viral loads and undetectable anti-HEV IgG and IgM antibodies.

SIGNIFICANCE AND IMPACT OF THE STUDY

Hepatitis E virus genotype 3 (HEV GT3) has been associated with silent chronic hepatitis and cirrhosis in HIV-positive subjects worldwide, but there is a lack of data on this co-infection in Brazil.

Hepatitis E: A Literature Review

Hepatitis E is the fifth known form of human viral hepatitis. Although not very common in our clinical practice, the incidence in Western countries is increasing. Infection with the hepatitis E virus (HEV) may be related to acute illness, liver failure, chronic hepatitis and cirrhosis. HEV itself is an RNA virus, with eight described genotypes (HEV 1-8), four of which more commonly affect humans and have, thus, been better studied. Besides liver manifestations, genotype 3 is also related to extra-hepatic manifestations, such as neurological, renal and rheumatological. Evolution to chronic disease occurs especially in patients who underwent transplantation, have hematological malignancies requiring chemotherapy, or have infection with the human immunodeficiency virus. The diagnosis may be difficult because of the low availability of tests and due to low sensibility and specificity. The acute form of illness does not have to be treated, but the chronic one does. We present here a literature review of hepatitis E and the relation between chronic hepatitis E and transplantation.

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

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

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.

Hepatitis E virus infection in patients with acute non-A, non-B, non-C hepatitis in Central Brazil

Hepatitis E virus (HEV) infection has a worldwide distribution and represents an important cause of acute hepatitis. This study aims to investigate the occurrence of HEV infection and factors associated with this infection in patients with acute non-A, non-B, non-C hepatitis in Central Brazil. From April 2012 to October 2014, a cross-sectional study was conducted among 379 patients with acute non-A, non-B, non-C hepatitis in the City of Goiania, Central Brazil. Serum samples of all patients were tested for serological markers of HEV infection (anti-HEV IgM and IgG) by ELISA. Positive samples were confirmed using immunoblot test. Anti-HEV IgM and IgG positive samples were tested for HEV RNA. Of the 379 serum samples, one (0.3%) and 20 (5.3%) were positive for anti-HEV IgM and IgG, respectively. HEV RNA was not found in any sample positive for IgM and/or IgG anti-HEV. After multivariate analysis, low education level was independently associated with HEV seropositivity (p = 0.005), as well as living in rural area, with a borderline p-value (p = 0.056). In conclusion, HEV may be responsible for sporadic self-limited cases of acute hepatitis in Central Brazil.

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.