• COVID-19
• Diagnosis
• Epidemiology
• Hepatitis E
• Vaccination

• Humans
• COVID-19/prevention & control
• COVID-19/immunology
• COVID-19/epidemiology
• Republic of Korea/epidemiology
• Immunoglobulin M/blood
• Hepatitis E/epidemiology
• Hepatitis E/immunology
• Male
• COVID-19 Vaccines/immunology
• Female
• Disease Outbreaks
• Adult
• SARS-CoV-2/immunology
• Hepatitis E virus/immunology
• Middle Aged
• False Positive Reactions
• Hepatitis Antibodies/blood
• RNA, Viral
• Vaccination/statistics & numerical data

• diseases
• gastroenterology

• Humans
• Male
• Acute Disease
• Epstein-Barr Virus Infections
• Hepatitis Antibodies
• Hepatitis E/diagnosis
• Hepatitis E/epidemiology
• Hepatitis E virus/genetics
• Herpesvirus 4, Human
• Immunoglobulin M
• Prospective Studies
• Republic of Korea/epidemiology
• Female
• Adult

• Korea Disease Control and Prevention Agency

• Greece
• HEV RNA
• dialysis
• epidemiology
• hemodialysis
• hepatitis E virus
• prevalence
• risk factors
• seroprevalence

• Asymptomatic infections
• Diseases outbreaks
• Hepatitis E
• Korea

• HEV
• antibody
• farmworkers
• seroprevalence

Although acute hepatitis E is not fatal in healthy individuals, it is unclear whether hepatitis E superinfection increases the mortality in patients with pre-existing liver disease. Thus, we investigated the prognosis of patients with acute hepatitis E according to their cirrhosis diagnosis, and the prognosis according to the development of acute-on-chronic liver failure (ACLF) in patients with cirrhosis and chronic liver disease (CLD).

This study included 74 consecutive patients who were diagnosed with acute viral hepatitis E between January 2007 and December 2019. Of them, 39 patients without CLD, 13 patients with non-cirrhotic CLD, and 22 patients with cirrhotic CLD were analyzed.

Among the 74 patients with HEV infection, 7 (9.5%) died within 180 days: 5 with underlying cirrhosis (71.4%) and 2 without cirrhosis (28.6%). The 180-day mortality was significant higher for patients with cirrhosis than for patients without cirrhosis (22.7% vs. 3.8%, P = 0.013). The age- and sex-adjusted proportional-hazard model revealed an approximately eightfold increase in the 180-day mortality risk in patients with cirrhosis compared to patients without cirrhosis. In addition, development of hepatitis E virus-related ACLF due to acute liver function deterioration in patients with pre-existing CLD or cirrhosis worsened the 180-day mortality rate.

Our findings suggest that the acute hepatitis E mortality rate was low in healthy individuals but higher in patients with cirrhosis, and especially high in those with ACLF.

The online version contains supplementary material available at 10.1186/s12879-022-07050-w.

• Acute and chronic hepatitis
• Blood transfusion
• Hepatitis E virus
• Immunosuppression
• Transplantation

• Blood Donors
• Blood Transfusion
• Hepatitis Antibodies
• Hepatitis E/diagnosis
• Hepatitis E/drug therapy
• Hepatitis E/epidemiology
• Hepatitis E virus/genetics
• Humans
• RNA, Viral

Despite the increasing relevance of Hepatitis E, an emerging disease endemic in developing and with increasing numbers of sporadic cases in industrialized countries, commercial tests are mainly based on batch oriented serological assays. In this retrospective study, we compared a line immunoassay (LIA; recomLine HEV, Mikrogen) and an ELISA (EIA; Anti-Hepatitis E Virus ELISA, Euroimmun) with a novel chemoluminescence immunoassay in a monotest format (CLIA; Hepatitis E VirClia, Vircell). Twenty sera of PCR proven cases of hepatitis E and 68 blood samples serologically pre-characterized were included. Applying the WHO reference standard, the CLIA demonstrated the highest analytical sensitivity for IgG and IgM. The combinations of CLIA/EIA (IgG and IgM) and CLIA/LIA (IgG) measurements showed substantial correlation. Compared to overall antibody detection (seropositivity in ≥2 assays), CLIA correlation was excellent, outperforming LIA (IgM) and EIA (IgG and IgM). Minor IgM cross reactivity in samples of patients with acute EBV infection was observed in all three assays. The CLIA showed good performance in diagnostic samples compared to established LIA and EIA assays. Due to its ready-to-use monotest format, the CLIA allows simple, time- and cost-effective handling of single samples. These qualities make the assay suitable for diagnostics, especially in the emergency setting and for low-throughput laboratories.

• CLIA
• ELISA
• HEV
• LIA
• antibody
• hepatitis E virus
• monotest
• serology

Hepatitis E virus (HEV) is an emerging zoonotic pathogen and an important cause of acute viral hepatitis in European countries. Corsica Island has been previously identified as a hyperendemic area for HEV.

Our aim was to characterise the prevalence and titres of IgG antibodies to HEV among blood donors on Corsica and establish a model of the annual force of infection.

Between September 2017 and January 2018, 2,705 blood donations were tested for anti-HEV IgG using the Wantai HEV IgG enzyme immunoassay.

The overall seroprevalence was 56.1%. In multivariate analysis, seroprevalence was higher in men than in women (60.0% vs 52.2%; p < 0.01), increased with age and was significantly higher among donors born on Corsica (60.6% vs 53.2%; p < 0.01). No significant difference was observed between the five districts of the island. IgG anti-HEV titres were mostly low (70% of positive donors had titres < 3 IU/mL). In Corsican natives, increasing seroprevalence by age could be explained by models capturing a loss of immunity (annual probability of infection: 4.5%; duration of immunity: 55 years) or by age-specific probabilities of infection (3.8% for children, 1.3% for adults).

We confirmed the high HEV seroprevalence on Corsica and identified three aspects that should be further explored: (i) the epidemiology in those younger than 18 years, (ii) common sources of contamination, in particular drinking water, that may explain the wide exposure of the population, and (iii) the actual protection afforded by the low IgG titres observed and the potential susceptibility to secondary HEV infection.

• Blood donors
• Corsica
• Epidemiology
• Hepatitis E virus
• IgG titres
• Seroprevalence

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.

•

No data from 50% of African countries

• Hepatitis E virus
• High-volume testing
• Quantitative assay

Clinical diagnosis of hepatitis E viral (HEV) infection mainly relies on serological assays, and the current status of misdiagnoses regarding HEV infection is uncertain. In this study, patients with acute HEV infection were tested for anti-HEV IgM and IgG, a HEV antigen (Ag), and viral loads (HEV RNA). Serology was performed using four commercial HEV ELISA kits: Wantai, Kehua, Lizhu, and Genelabs IgM and IgG. The HEV RNA was detected using RT-PCR assays. The sensitivities of different kits for anti-HEV IgM ranged from 82.6% to 86%. Each kit for anti-HEV IgM was highly specific (97.8–100%). The sensitivities of all kits to detect anti-HEV IgG with (87.2–91.9%) had a substantial agreement, but the Kehua and Genelabs tests were more specific than the Wantai and Lizhu tests. The Wantai tests for the HEV Ag and HEV RNA were also important for acute HEV infections (Kappa = 0.787). Furthermore, a total of 6.98% of HEV infections were positive for HEV RNA but negative for both the HEV Ag and anti-HEV antibodies of IgM and IgG classes. Our findings demonstrate that the diagnosis of hepatitis E may be missed if only serological assays are used. Thus, a combination of serological and nucleic acid testing provides the optimal sensitivity and specificity to the diagnostic process.

• HEV genotype
• blood donors
• chronic hepatitis
• chronic kidney disease
• hemodialysis and organ transplantation
• hepatitis E virus
• prevention
• seroprevalence
• transfusion transmission

• Blood Transfusion/methods
• Blood Transfusion/trends
• Hepatitis E/complications
• Hepatitis E/physiopathology
• Hepatitis E virus/pathogenicity
• Humans
• Organ Transplantation/methods
• Organ Transplantation/trends
• Renal Dialysis/methods
• Renal Dialysis/trends

The Hepatitis E virus (HEV) is an emergent virus that causes acute hepatitis in immunocompetent hosts and chronic hepatitis in immunocompromised hosts. In Latin America, the main circulating genotype HEV-3 is usually of zoonotic origin. Diagnosis and seroprevalence studies mainly rely on the detection of specific antibodies. There are scarce data on the seroprevalence of HEV infection in Latin America mainly due to the lack of awareness of HEV circulation. Furthermore, in some countries, like Argentina, HEV testing is not included in routine assays. In order to provide tools to deepen the knowledge on HEV epidemiology in South America, we designed a new in-house ELISA based on the native recombinant protein ORF2 aa112–608 and demonstrated its potential for detecting anti-HEV immunoglobulin G (IgG) in human serum samples. The following conditions were determined: an optimal antigen concentration of 0.25 μg/ml, a serum dilution of 1:80, gelatin as a blocking agent, and a secondary antibody dilution of 1:2000. A relative sensitivity of 93.33% (95% CI: 77.9–99.2%) and a relative specificity of 99.4% (95% CI: 96.7–100%) were determined using a panel of previously characterized sera and a gold standard (HEV IgG ELISA, DIA.PRO, Italy). Further, we obtained a very good agreement (κ index = 0.94, 95% CI: 0.87–1.00) with the gold standard. We screened 813 blood donor samples with this newly developed ELISA and found a seroprevalence of 9.23% (95% confidence interval, 7.33–11.43%). We show for the first time evidence of past HEV infection in Tucuman, the most populated city in northern Argentina. We expect that this study will raise the interest of health decision makers who should intercede to include indirect testing of HEV in regular diagnostic protocols. In conclusion, the in-house ELISA developed in this work shows a very good agreement with an already licensed commercial HEV IgG ELISA (DIA.PRO, ITALY), which can be used as an epidemiologic tool for HEV surveillance.

• blood donors
• enzyme-linked immunosorbent assay
• hepatitis E virus
• recombinant protein
• seroprevalence

• ELISA
• Turkey
• hepatitis E virus
• seroprevalence
• total anti-HEV Ab
• viral hepatitis

• Hepatitis E/epidemiology
• Hepatitis E virus/physiology
• Humans
• Seroepidemiologic Studies

• Enzyme-linked immunosorbent assay
• Hepatitis
• Hepatitis E virus
• Immunoglobulin G
• Seroepidemiologic study

Although Hepatitis E is increasingly described as a major cause of liver disease in industrialized countries, the epidemiology is far from being fully elucidated. We provide here a comprehensive review of documented clusters of cases, and of serological studies conducted in populations with distinct types of exposure. Seroprevalence rates range from <5% to >50% depending on the countries and the groups of population. Such discrepancies can be attributed to the type of serological assay used, but this solves only a part of the problem. We performed a meta-analysis of studies performed with the broadly used Wantai HEV-IgG ELISA and found striking differences that remain difficult to understand with the current knowledge of transmission pathways.

• Hepatitis E virus
• Meta-analysis
• epidemiology
• industrialized countries
• seroprevalence

• HEV
• RNA viremia
• diagnosis
• serology
• seroprevalence

• Anti-HEV IgG
• Genotype
• Hepatitis E
• Hepatitis E virus
• Outbreak
• Prevalence
• Reservoir

• HEV
• blood donors
• seroprevalence
• transfusion
• viremia

• Conformational epitopes
• Diagnostic
• HEV ORF2 capsid
• Mimotopes
• Phage display
• Vaccine

• Antibodies, Neutralizing/immunology
• Antibodies, Viral/immunology
• Capsid/immunology
• Diagnostic Tests, Routine/methods
• Drug Discovery
• Epitopes/immunology
• Hepatitis E virus/immunology
• Humans
• Peptide Library
• United Kingdom
• Viral Vaccines/immunology
• Viral Vaccines/isolation & purification

Hepatitis E virus (HEV) is transfusion-transmissible and therefore poses a risk to blood transfusion safety. Seroprevalence studies are useful for estimating disease burden and determining risk factors. Considerable variability in the sensitivity of HEV antibody detection assays exists. This study aimed to compare the performances of commercially available HEV enzyme-linked immunosorbent assays (ELISA) in Australian blood donor samples. Plasma samples that tested positive (n = 194) or negative (n = 200) for HEV IgG (Wantai HEV IgG ELISA) were selected. Of the 194 HEV IgG positive samples, 4 were positive for HEV IgM (Wantai HEV IgM ELISA). All samples were tested with the MP Diagnostics: HEV IgG ELISA, total (IgG, IgM, and IgA) HEV antibody ELISA, and HEV IgM ELISA. Of the 194 Wantai HEV IgG positive samples, 92 (47%) tested positive with the MP Diagnostics HEV IgG ELISA (κ = 0.47) and 126 (65%) with MP Diagnostics total HEV antibody assay (κ = 0.65). There was poor agreement between Wantai and MP Diagnostics HEV IgM assays. This study demonstrated poor agreement between the assays tested. These observations are consistent with previous reports demonstrating significant variability between HEV ELISAs, highlighting that results of HEV serology should be interpreted with caution.

• Germany
• Hepatitis E/epidemiology
• Hepatitis E/virology
• Hepatitis E virus/classification
• Hepatitis E virus/genetics
• Hepatitis E virus/isolation & purification
• Humans
• Prevalence
• Risk Factors

Infection with hepatitis E virus (HEV) in immunocompromised patients can lead to severe liver disease. Treatment options for HEV include peginterferon or ribavirin, routinely also used for the treatment of hepatitis C virus (HCV) infection.

We determined the prevalence and clinical consequences of HEV in United States (US) based patients who underwent liver transplantation (LT) for chronic HCV.

Seroprevalence of HEV in 145 US LT recipients with a history of chronic HCV was determined pre-LT, 1, 3 and 5 years post-LT. All last available samples and all samples in IgM positive patients and post-LT IgG seroconverters were tested for HEV RNA.

Overall anti-HEV seroprevalence was 42 %. Five patients were HEV IgM positive pre-LT, one patient had IgM seroconversion post-LT and eight patients had IgG seroconversion post-LT. None of the tested samples were positive for HEV RNA. Eight out of nine of the post-LT seroconverters had been treated for HCV recurrence before or at the moment of seroconversion.

LT recipients in the US are at risk of acquiring HEV. Post-LT HCV treatment with interferons and/or ribavirin may have protected patients against chronic HEV. With the arrival of new direct antiviral agents for the treatment of HCV and the elimination of peginterferon and ribavirin from HCV treatment regimens, the prevalence of chronic HEV in this population may rise again.

The seroprevalence of hepatitis E virus (HEV) among high-risk groups overseas is high, but studies in these groups are rare in South Korea. We conducted the present study from April to November 2012 to obtain data on the seroprevalence and associated risk factors for HEV among slaughterhouse workers in South Korea.

Slaughterhouse workers from 80 workplaces nationwide were surveyed in South Korea in 2012. The subjects comprised 1848 cases: 1434 slaughter workers and 414 residual products handlers. By visiting 80 slaughterhouses, which were mixed with 75 of which also performed residual products handling, we conducted a questionnaire survey for risk factors and obtained blood samples in order to determine the seropositivity and seroprevalence of HEV. Anti-HEV IgG and IgM were measured using HEV IgG and IgM enzyme-linked immunospecific assay kits and HEV antigen was measured by reverse transcription polymerase chain reaction (RT-PCR).

The seropositivity of anti-HEV IgG was 33.5% (slaughter workers 32.8% and residual products handlers 36.2%), and among the seropositive individuals the seroprevalence of anti-HEV IgM was 0.5% (slaughter workers 0.5%, residual products handlers 0.7%). The response rate of HEV-antigen as measured by RT-PCR was 0.2%. Risk factors significantly related to anti-HEV IgG seropositivity were age, sex , and working duration (slaughter workers only).

There were significant risk factors (sex, age, and working duration) for HEV identified in our study. All three positive cases for HEV-antigen by RT-PCR were related to pig slaughter but without statistical significance. To prevent HEV, an educational program and working guidelines may be needed for high risk groups.

• Hepatitis E
• Risk factors
• Seroprevalence
• Slaughterhouse
• Zoonoses

Hepatitis E virus (HEV) is an emerging pathogen associated with endemic and acute viral hepatitis. In this study, we investigate the HEV seroprevalence and putative risk factors by a nationwide cross-sectional study in the Republic of Korea.

The prevalence of anti-HEV antibody was investigated in 2,450 serum samples collected in fourth Korea National Health and Nutrition Examination Survey. In addition, epidemiological information on possible risk factors including gender, age, education, occupation, and residence location for exposure to HEV was obtained.

The frequency of anti-EIA reactive sample was 5.9% (144/2450). The individuals in groups with male, older age, low education level and living in rural or coastal regions had high seroprevalence estimates (P ≤ 0.001). In addition, seroprevalence was significantly higher among individuals with self-identified skilled agricultural, forestry, and fishery workers (31.3%, P < 0.001).

This study provides valuable data that could be used to investigate associations of HEV seroprevalence and putative risk factors by a nationwide cross-sectional study. The high HEV seroprevalence of skilled agricultural, forestry, and fishery workers and individuals lived in coastal and rural area indicated that zoonotic transmission is an important risk factor for HEV infection in the republic of Korea. Further studies that include detailed and continuous nationwide surveys are required to identify unrecognized risk factors and to monitor the HEV infection prevalence.

The online version of this article (doi:10.1186/1471-2334-14-517) contains supplementary material, which is available to authorized users.

• Age
• Blood donor
• China
• HEV
• Seroprevalence

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

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

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

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

• Blood donors
• hepatitis E virus
• seroprevalence

Hepatitis E virus (HEV) infection is widespread in China, but few studies have been carried out in Guangdong Province. This study aimed to characterize the prevalence of HEV infections among swine, swine farmers and the general population in Guangdong Province. We conducted an epidemiological study that included swine, swine farmers and health examination attendees in Guangdong from 2011 to 2013. The overall seroprevalence of anti-HEV antibodies in swine was 64.7%. The results revealed that growing pigs, sows and boars (OR ranges from 3.5 to 21.5) have a higher risk than nursery pigs. HEV RNA in swine bile showed that HEV is epidemic in swine in the Pearl River Delta, with the highest prevalence of 22.73% in Foshan. Some genomes of HEV strains from each district were sequenced. Phylogenetic analysis of partial open reading frame 2 (ORF2) shows that they belong to genotype IV and are most closely related to isolates from China. In total, 307 participants were enrolled in the study, including 114 swine farmers and 193 attendees from hospitals. IgG anti-HEV was detected in 48.25% of swine farmers and in 38.34% of the general population. Seroprevalence rates were almost stratified by age, with a higher positive rate for males compared to females across all age groups. Women on swine farms appeared to have a lower risk of infection compared to the general population, revealing that the risk factors for HEV infection are not unique. The results suggested that there were other risk factors for HEV infection. HEV infection is prevalent in Guangdong, but due to the small sample sizes, more investigations are needed to assess the potential impact of HEV infection, and many additional risk factors should be considered.

• Adult
• Animal Husbandry
• Animals
• Antibody Specificity/immunology
• Base Sequence
• Bile/virology
• China/epidemiology
• Female
• Geography
• Hepatitis Antibodies/immunology
• Hepatitis E/epidemiology
• Hepatitis E/immunology
• Hepatitis E/virology
• Hepatitis E virus/immunology
• Hepatitis E virus/physiology
• Humans
• Immunoglobulin G/immunology
• Male
• Middle Aged
• Molecular Sequence Data
• Odds Ratio
• Phylogeny
• Prevalence
• RNA, Viral/isolation & purification
• Swine/virology
• Swine Diseases/epidemiology
• Swine Diseases/virology

Swine hepatitis E virus (HEV) is widespread throughout pigs in both developing and industrialized countries. This virus is an important zoonotic agent and a public concern worldwide. Infected pigs are asymptomatic, so diagnosing swine HEV relies on detection of the virus or antibodies against the virus. However, several obstacles need to be overcome for effective and practical serological diagnosis. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) that used a purified recombinant capsid protein of swine HEV. The potential clinical use of this assay was evaluated by comparing it with a commercial kit (Genelabs Technologies, Diagnostics, Singapore). Results of the ELISA were highly correlated with those of the commercial kit with a sensitivity of 97% and specificity of 95%. ROC (receiving operator characteristic) analysis of the ELISA data produced a value of 0.987 (95% CI, 0.977~0.998, p < 0.01). The cut-off value for the ELISA was also determined using negative pig sera. In summary, the HEV-specific ELISA developed in the present study appears to be both practical and economical.

• ELISA
• diagnosis
• swine hepatitis E virus

• AUC
• CMV
• Diagnostics
• EBV
• ELISA
• Epstein–Barr virus
• HAV
• HBV
• HCV
• HEV
• Hepatitis E virus
• Immune response
• Immunocompromised
• LIMS
• OD
• ORF
• RNA
• ROC
• RT-PCR
• S/N
• Transplantation
• WHO
• World Health Organization
• area under the curve
• cytomegalovirus
• enzyme linked immunosorbent assay
• hepatitis A virus
• hepatitis B virus
• hepatitis C virus
• hepatitis E virus
• laboratory information management system
• open reading frame
• optical density
• receiver operator curve
• reverse transcriptase polymerase chain reaction
• ribonucleic acid
• signal to noise

Hepatitis E virus (HEV) is an emerging pathogen. We evaluated the seroprevalence of HEV infection among swine farmers and the general population in Taiwan, a nonendemic country.

We conducted a cross-sectional seroepidemiologic study in rural Taiwan in 2012 and 2013. The study included swine farmers, health examination attendees, pregnant women, and students. A commercial enzyme-linked immunosorbent assay was used to detect immunoglobulin G (IgG) and IgM against HEV. Pertinent information was collected using a questionnaire.

In total, 660 participants were enrolled in the study, including 156 swine farmers, 314 health examination attendees, 100 pregnant women, and 90 students. IgG anti-HEV was detected in 29.5% of swine farmers, 11.5% of health examination attendees, 2% of pregnant women, and 1.1% of students. Two subjects were positive for IgM anti-HEV. Logistic regression analysis revealed that swine farmers had an approximately 3.5-fold increased risk (odds ratio [OR], 3.46; 95% confidence interval [CI], 1.91–6.27; p<0.0001) for being seropositive for IgG anti-HEV as compared to the general population. Age was positively associated with seropositive rate (OR, 1.07 per year; 95% CI, 1.05–1.09; p<0.0001).

HEV infection is prevalent in Taiwan. The seroprevalence of HEV infection is high in swine farmers and in the elderly population.

• Adult
• Animals
• Farmers/statistics & numerical data
• Female
• Hepatitis E/epidemiology
• Hepatitis E virus/immunology
• Hepatitis E virus/physiology
• Humans
• Immunoglobulin G
• Male
• Rural Population/statistics & numerical data
• Seroepidemiologic Studies
• Swine/virology
• Taiwan/epidemiology

• Antibodies, Viral/blood
• Hepatitis E/blood
• Hepatitis E/diagnosis
• Hepatitis E/immunology
• Hepatitis E virus/genetics
• Hepatitis E virus/immunology
• Humans
• RNA, Viral/blood