Antibodies to hepatitis E virus among several populations in Greece: increased prevalence in an hemodialysis unit

HEV Infection in Beta-Thalassemia Patients

Thalassemia is an inherited hematological disorder characterized by a decrease in the synthesis of or absence of one or more globin chains. Hepatitis E virus (HEV) is a major cause of acute viral hepatitis, constituting a major global health burden and emerging as a critical public health concern. HEV infection is mainly transmitted via the fecal-oral route; however, parenteral transmission through blood components has been reported in both developing and developed countries. Although HEV infection is typically self-limiting, immunocompromised individuals, patients with chronic liver disease, and thalassemic patients are at a heightened risk of contracting the infection and may develop chronic hepatitis and life-threatening complications that require treatment. The reported prevalence rates of HEV in thalassemia patients vary significantly by country. Age, gender, residential area, and the cumulative amount of blood transfusions received have been identified as associated risk factors for HEV infection. In order to enhance blood safety and ensure the protection of vulnerable patient populations, such as thalassemia patients, several countries have introduced universal or targeted HEV screening policies in blood donations. Other preventive measures include vigilant monitoring of thalassemic patients and screening for anti-HEV antibodies. The aim of this review is to explore the prevalence, risk factors, clinical impact and management of HEV infection in patients with thalassemia.

Testing Hepatitis E Seroprevalence among HIV-Infected Patients in Greece: The SHIP Study

Hepatitis E virus (HEV) poses significant health concerns worldwide, particularly among people living with HIV (PLWHIV), due to an increased risk of chronic infection and progression to cirrhosis in individuals with low CD4 cell counts. This study aimed to investigate the prevalence, chronicity potential, and risk factors of HEV infection among PLWHIV in Greece, where data are currently absent. A synchronic multicentric study encompassing five major Greek university hospitals was executed over 24 months, recruiting 696 PLWHIV participants. The prevalence of HEV IgG antibodies was 16.5%, with 8.6% showing evidence of acute HEV infection (HEV IgM). Active viral replication (HEV RNA) was present in 2.3% of the study population. Longitudinal analysis revealed that of the 25 initially anti-HEV IgM-positive individuals, only 3 seroconverted to IgG positivity, and among those with prior HEV RNA positivity (16), none showed evidence of active replication in subsequent tests. Comparative subgroup analysis highlighted the lack of significant differences in HIV-related parameters between HEV seropositive and seronegative individuals. Laboratory evaluations generally showed no significant disparities across most parameters; however, a higher seropositivity for Hepatitis A was observed in the HEV-positive subgroup. Our findings highlight a considerable prevalence of HEV among PLWHIV in Greece, with no observed cases of chronicity.

Hepatitis E Virus (HEV) Infection among Hemodialysis Patients from Southern Bulgaria

Viral hepatitis B and C are widely recognized problems in hemodialysis (HD) patients. There have been increasing reports of the importance of the hepatitis E virus (HEV) in recent years, but the worldwide data on the seroprevalence of HEV among them are conflicting. The aim of the present study was to assess the seroprevalence of HEV in HD patients and to analyze the predictors of seropositivity. This study was conducted in 2020 in the central part of southern Bulgaria. A total of 225 patients were enrolled. An enzyme-linked immunosorbent assay for the determination of anti-HEV IgM/IgG was used. All patients were tested for the presence of HEV RNA. Anti-HEV IgM alone and anti-HEV IgG alone were found in 6 (2.7%) and 14 (6.2%) patients, respectively, and in 4 (1.8%) patients, they were found simultaneously. All patients were HEV RNA-negative. The overall HEV seroprevalence was 10.7% (24/225). The binominal logistic regression analysis of available predictors confirmed the role of vascular access and a duration of dialysis treatment over 5 years as predictors significantly associated with increased risk for HEV, and the consumption of bottled water with lower levels of HEV IgG seroprevalence among hemodialysis patients. The accumulated data are the basis for comparative analysis in subsequent trials in the same dialysis centers and for enhancing the range of screening markers used in this particular patient group.

Hepatitis E Virus (HEV) Infection in Hemodialysis Patients: A Multicenter Epidemiological Cohort Study in North-Eastern Greece

Hepatitis E virus (HEV), a common cause of viral hepatitis in developing countries, is mainly transmitted via the fecal-oral route, but also may be a prevalent hospital-transmitted agent among patients on regular hemodialysis due to parenteral transmission. Previous epidemiological studies among hemodialysis patients in Greece, using different diagnostic techniques, gave conflicting results. Τhe present study aimed to measure the exposure rate of hemodialysis patients of north-eastern Greece to HEV by estimating the overall seroprevalence, and to identify potential risk factors. Serum samples from all patients attending the hemodialysis centers of north-eastern Greece (n = 6) were tested for the presence of anti-HEV IgG antibodies using a modern and sensitive ELISA (Enzyme-linked Immunosorbent Assay) technique (Wantai). In total, 42 out of 405 hemodialysis patients were positive for anti-HEV IgG (10.4%), while all samples were negative for HEV RNA when tested using nested RT-PCR. HEV seropositivity among hemodialysis patients was significantly associated with area of residence and contact with specific animals (pork, deer). No association was found with religion, gender distribution and hemodialysis duration. This study showed an increased seroprevalence of HEV among hemodialysis patients in Greece. Agricultural or livestock occupation and place of residence seem to be independent factors that increase the risk of HEV infection. In conclusion, HEV infection calls for the regular screening of hemodialysis patients regardless of the hemodialysis duration or clinical symptoms.

Higher Risk of HEV Transmission and Exposure among Blood Donors in Europe and Asia in Comparison to North America: A Meta-Analysis

Background and aims: The increasing number of diagnosed hepatitis E virus (HEV) infections in Europe has led to the implementation of the testing of blood products in various countries. Many nations have not yet implemented such screening. To assess the need for HEV screening in blood products worldwide, we conducted a systematic review and meta-analysis assessing HEV RNA positivity and anti-HEV seroprevalence in blood donors. Methods: Studies reporting anti-HEV IgG/IgM or HEV RNA positivity rates among blood donors worldwide were identified via predefined search terms in PubMed and Scopus. Estimates were calculated by pooling study data with multivariable linear mixed-effects metaregression analysis. Results: A total of 157 (14%) of 1144 studies were included in the final analysis. The estimated HEV PCR positivity rate ranged from 0.01 to 0.14% worldwide, with strikingly higher rates in Asia (0.14%) and Europe (0.10%) in comparison to North America (0.01%). In line with this, anti-HEV IgG seroprevalence in North America (13%) was lower than that in Europe (19%). Conclusions: Our data demonstrate large regional differences regarding the risk of HEV exposure and blood-borne HEV transmission. Considering the cost–benefit ratio, this supports blood product screening in high endemic areas, such as Europe and Asia, in contrast to low endemic regions, such as the U.S.

Transfusion-transmitted hepatitis E: What we know so far?

Hepatitis E virus (HEV) is a major cause of viral hepatitis globally. There is growing concern about transfusion-transmitted HEV (TT-HEV) as an emerging global health problem. HEV can potentially result in chronic infection in immunocompromised patients, leading to a higher risk of liver cirrhosis and even death. Between 0.0013% and 0.281% of asymptomatic blood donors around the world have HEV viremia, and 0.27% to 60.5% have anti-HEV immunoglobulin G. HEV is infectious even at very low blood concentrations of the virus. Immunosuppressed patients who develop persistent hepatitis E infection should have their immunosuppressant regimen reduced; ribavirin may be considered as treatment. Pegylated interferon can be considered in those who are refractory or intolerant to ribavirin. Sofosbuvir, a nucleotide analog, showed modest antiviral activity in some clinical studies but sustained viral response was not achieved. Therefore, rescue treatment remains an unmet need. The need for HEV screening of all blood donations remains controversial. Universal screening has been adopted in some countries after consideration of risk and resource availability. Various pathogen reduction methods have also been proposed to reduce the risk of TT-HEV. Future studies are needed to define the incidence of transmission through transfusion, their clinical features, outcomes and prognosis.

Seroprevalence of Hepatitis E Virus Infection among Blood Donors in Bulgaria

Hepatitis E virus (HEV) infection is widespread among domestic pigs, industrial swine, and wild boars in Bulgaria. The aim of the current research was to present the HEV seroprevalence among blood donors in Bulgaria. In the present study, 555 blood donors (479 males and 76 females) were enrolled from five districts in the country (Shumen, Pleven, Stara Zagora, Plovdiv, and Sofia districts). All blood samples were tested for anti-HEV IgG using the recomWell HEV IgG ELISA test (Mikrogen GmbH, Neuried, Germany). Each participating donor completed a short, structured, and specific questionnaire to document data on the current study. Anti-HEV IgG positive results were detected in 144 (25.9%) blood donors, including 129 (26.9%) males and 15 (19.7%) females. The established HEV seropositivity was 28.8% (23/80) in Shumen district, 23.2% (22/95) in Pleven district, 27.1% (38/140) in Stara Zagora district, 27.5% (44/160) in Plovdiv district, and 21.3% (17/80) in Sofia district. A high HEV seroprevalence was found for persons who declared that they were general hunters (48.7%; 19/39; p = 0.001) and hunters of wild boars (51.6%; 16/31; p = 0.001). We present the first seroprevalence rates of HEV infection in blood donors from Bulgaria. The results of our research showed high HEV seropositivity among blood donors.

Epidemiology, diagnosis, vaccines, and bibliometric analysis of the 100 top-cited studies on Hepatitis E virus

INTRODUCTION

In low-income countries, Hepatitis E infection is a common cause of acute hepatitis. So far, only two recombinant vaccines (rHEV and HEV 239) have been developed against Hepatitis E virus (HEV). Of which HEV 239 is licensed in China, but is not yet available in any other country.

OBJECTIVE

This study aims to discuss epidemiology, diagnosis, available vaccines for HEV, and provides an overview of 100 top-cited studies on HEV.

METHODS

A bibliometric analysis was conducted on the topic "HEV" through a systematic search of the Web of Science. The keywords used were "Hepatitis E" and retrieved articles were assessed for number of attributes.

RESULTS

The search returned a total of 3,235 publications, cited 95,858 times with h-index 129. The main finding for the 100 top-cited articles on HEV showed: number of authors ranging from 1 to 23, cited references range from 4 to 304, global citations score per year range from 6.61 to 175, and global citations score range from 148 to 791. Of the 100 top-cited studies, the authors who published most articles are Purcell (n = 18), Meng (n = 17), and Emerson (n = 15). Most The largest share of articles on HEV was contributed by United States of America (n = 49) with 12,795 citations. The National Institute of Allergy andInfectious Diseases was leading institute with greatest number of publications (n = 16), cited 3,950 times.

CONCLUSIONS

The studies conducted on HEV have increased over time. The information presented would be very useful in decision making for policy makers providing health care, and for academicians in providing a reference point for future research.

Seroepidemiology of hepatitis E virus infection in patients undergoing maintenance hemodialysis: Systematic review and meta-analysis

Patients undergoing regular hemodialysis (HD) are at an extreme risk of acquiring bloodstream infections compared to the general population. Hepatitis E virus (HEV) infection is an important emerging health issue in these patients. To date, numerous studies have investigated the seroprevalence of HEV among HD patients across the world; however, the data are conflicting. The present study aimed to measure the exposure rate of HD patients to HEV infection by estimating the overall seroprevalence of HEV in this high-risk group. A systematic literature search was carried out using five electronic databases from inception to January 10, 2020, with standard keywords. Pooled seroprevalence estimates with 95% confidence intervals (CIs) were calculated using a random intercept logistic regression model. The seroprevalence of HEV increased from 6.6% between the years of 1994 and 2000 to 11.13% from 2016 to 2020. Blood transfusion was associated with a nearly 2-fold increase in the rate of HEV seropositivity (OR = 1.99; 95% CI: 1.50-2.63, P < .0001, I² = 6.5%). HEV seroprevalence among patients with HD for more than 60 months was significantly higher than those with HD for less than 60 months (27.69%, 95% CI: 20.69%-35.99% vs 15.78%, 95%CI: 8.85%-26.57%, respectively) (P = .06). Our results indicated increased exposure of HD patients with HEV infection over the last decade. We concluded that blood transfusion and duration of HD are considerable risk factors for acquiring HEV infection among HD patients.

Prevalence of anti-hepatitis E virus IgG antibodies in sera from hemodialysis patients in Tripoli, Lebanon

Hepatitis E virus (HEV) is an important global public health concern. Several studies reported a higher HEV prevalence in patients undergoing regular hemodialysis (HD). In Lebanon, the epidemiology of HEV among HD patients has never been investigated previously. In this study, we examine the seroprevalence of HEV infection among 171 HD patients recruited from three hospital dialysis units in Tripoli, North Lebanon. Prevalence of anti-HEV IgG antibodies was evaluated in participant's sera using a commercial enzyme-linked immunosorbent assay (ELISA). The association of socio-demographic and clinical parameters with HEV infection in patients was also evaluated. Overall, 96 women and 75 men were enrolled in this study. Anti-HEV IgG antibodies were found positive in 37/171 HD patients showing a positivity rate of 21.63%. Among all examined variables, only the age of patients was significantly associated with seropositivity (P = 0.001). This first epidemiological study reveals a high seroprevalence of HEV infection among Lebanese HD patients. However, further evaluations that enroll larger samples and include control groups are required to identify exact causative factors of the important seropositivity rate in this population.

Seroepidemiology of hepatitis E in patients on haemodialysis in Croatia

PURPOSE

Data on the seroprevalence of hepatitis E virus (HEV) in heamodialysis (HD) patients are conflicting, ranging from 0 to 44%. The aim of this study was to determine the HEV seroprevalence and risk factors among HD patients in Croatia.

METHODS

A total of 394 HD patients from six medical facilities in five Croatian cities (three sites in the continental and three sites in the coastal region) were tested for HEV IgM/IgG antibodies using an enzyme-linked immunosorbent assay. Additionally, all samples were tested for HEV RNA by RT-PCR. Sociodemographic data and risk factors were collected using a questionnaire.

RESULTS

HEV IgG antibodies were detected in 110 (27.9%) patients. The seroprevalence varied significantly between dialysis centres, ranging from 5.2 to 43.4% (p = 0.001). HEV IgM antibodies were found in 0.04% of IgG positive patients. All patients tested negative for HEV RNA. Factors associated with HEV IgG seropositivity were age > 60 years (OR 8.17; 95% CI 1.08-62.14), living in the continental parts of the country (OR 2.58; 95% CI 1.55-4.30), and transfusion of blood products (OR 1.66; 95% CI 1.01-2.73). After adjusting for age and gender, patients from continental regions had higher odds of HEV seropositivity compared to patients from coastal regions (OR 2.88; 95% CI 1.71-4.85) and those who had RBC transfusions (OR 1.70, 95% CI 1.02-2.69) compared to those who did not.

CONCLUSION

The study showed a high HEV seropositivity among HD patients in Croatia, with significant variations between geographical regions. Continental area of residence and RBC transfusion were the most significant risk factors for HEV seropositivity. Due to the high seroprevalence, routine HEV screening among HD patients, especially in transplant candidates should be considered.

Epidemiology of hepatitis E in South-East Europe in the "One Health" concept

The significance of hepatitis E virus (HEV) as an important public health problem is rising. Until a decade ago, cases of HEV infection in Eur-ope were mainly confined to returning travelers, but nowadays, hepatitis E represents an emerging zoonotic infection in many European countries. The aim of this manuscript is to perform a systematic review of the published literature on hepatitis E distribution in humans, animals and environmental samples ("One Health" concept) in the South-Eastern European countries. Comparison of the available data showed that the anti-HEV seroprevalence in the South-Eastern Europe varies greatly, depending on the population studied, geographical area and methods used. The IgG seroprevalence rates in different population groups were found to be 1.1%-24.5% in Croatia, up to 20.9% in Bulgaria, 5.9-%17.1% in Romania, 15% in Serbia, up to 9.7% in Greece and 2%-9.7% in Albania. Among possible risk factors, older age was the most significant predictor for HEV seropositivity in most studies. Higher seroprevalence rates were found in animals. HEV IgG antibodies in domestic pigs were detected in 20%-54.5%, 29.2%-50%, 38.94%-50% and 31.1%-91.7% in Serbia, Bulgaria, Romania and Croatia, respectively. In wild boars seroprevalence rates were up to 10.3%, 30.3% and 31.1% in Romania, Slovenia and Croatia, respectively. A high HEV RNA prevalence in wild boars in some countries (Croatia and Romania) indicated that wild boars may have a key role in the HEV epidemiology. There are very few data on HEV prevalence in environmental samples. HEV RNA was detected in 3.3% and 16.7% surface waters in Slovenia and Serbia, respectively. There is no evidence of HEV RNA in sewage systems in this region. The available data on genetic characterization show that human, animal and environmental HEV strains mainly belong to the genotype 3.

Systematic review and meta-analysis of the seroprevalence of hepatitis E virus in the general population across non-endemic countries

BACKGROUND

Hepatitis E virus (HEV) has commonly been associated with large waterborne outbreaks of human jaundice in endemic areas but it has been increasingly recognised as a cause of sporadic human cases of jaundice in non-endemic areas, in individuals with no history of travel. Zoonotic exposure is widely hypothesized to be an important potential transmission route in these sporadic human cases. Serosurveys conducted to determine the frequency of HEV human exposure report wide ranges in prevalence across studies and locations. Our study objective was to compute meta-analysis summary estimates of human seroprevalence of HEV IgG within countries considered HEV non-endemic, where possible, and to determine whether this varied significantly across these countries, as well as investigating the role of potential HEV seroprevalence predictors such as population age structure.

MATERIALS AND METHODS

A broad literature search was conducted in six electronic databases. Citations were appraised, and relevant data extracted using forms designed and pre-tested a priori. Meta-analysis and meta-regression were conducted in R, with HEV IgG seroprevalence in blood donors or the general population being the outcome of interest, and country, assay, population age and sex structure, and chronological time investigated as predictors of the outcome.

RESULTS

From 4163 unique citations initially captured, data were extracted from 135 studies investigating HEV serology in blood donors or the general population, of 31 countries among those categorised as 'very high human development' by the United Nations. Country of sampling and assay employed were consistently significant predictors of HEV IgG seroprevalence with chronological time being a non-significant predictor in the dataset of captured studies.

CONCLUSIONS

While country of sampling and assay employed were significant predictors of HEV seroprevalence, comparison of HEV seroprevalence across non-endemic countries is hampered by the lack of a gold standard assay and uncertainty regarding residual bias across studies, as well as regional differences within some countries.

Systematic review with meta-analysis: the association between hepatitis E seroprevalence and haemodialysis

BACKGROUND

Hepatitis E virus (HEV) infection appears to be more common than previously thought. HEV seroprevalence in patients on maintenance haemodialysis (HD) is unclear with a range from 0% to 44%. In addition, risk factors of transmission of HEV in patients on haemodialysis are unknown.

AIM

To perform a systematic review and meta-analysis of HEV seroprevalence in HD patients compared with controls.

METHODS

A systematic search of several databases identified all observational studies with comparative arms. Two reviewers extracted data and assessed the methodological quality. A random-effects model was used for pooled odds ratio (OR) and 95% confidence interval (CI) of positive anti-HEV IgG in both groups. Heterogeneity and publication bias were assessed with appropriate tests.

RESULTS

We identified 31 studies from 17 countries between 1994 and 2016. Sixteen studies were judged to have adequate quality and 15 to have moderate limitations. HEV infection was more prevalent in patients on haemodialysis compared with controls (OR 2.47, 95% CI 1.79-3.40, I² = 75.2%, P < .01). We conducted several subgroup analyses without difference in results. Egger regression test did not suggest publication bias (P = .83). Specific risk factors of HEV transmission in patients on haemodialysis were not clearly identified.

CONCLUSIONS

Hepatitis E virus infection is more prevalent in patients on haemodialysis compared with non-haemodialysis control groups. Further studies are needed to determine risk factors of acquisition, impact on health, and risk for chronic HEV especially among those patients going to receive organ transplantation.

Hepatitis E in transfusion-dependent thalassaemia patients, in Greece: a single centre experience

Hepatitis E is considered an emerging disease that may be a threat in both developing and industrialized countries all over the world. The risk of chronic hepatitis E virus infection is higher among immunocompromised patients. This study aimed to assess the status of hepatitis E infection in patients with transfusion-dependent thalassaemia from a single centre, in Greece. Our results suggest that the prevalence of hepatitis E infection in this group of patients is low.

Hepatitis E virus: Infection beyond the liver?

Hepatitis E virus (HEV) infections are not limited to the liver but may also affect other organs. Several diseases, including Guillain-Barré syndrome, neuralgic amyotrophy, glomerulonephritis, cryoglobulinemia, pancreatitis, lymphoma, thrombopenia, meningitis, thyroiditis and myocarditis have been observed in the context of hepatitis E. To date, the definite pathophysiological links between HEV and extrahepatic manifestations are not yet established. However, it is suggested that HEV infection might be causative based on serological studies, case series, in vitro data and animal models. In particular, neuronal and renal diseases as well as pancreatitis seem to be caused by HEV, while a causative relationship between HEV and other diseases is more doubtful. Either direct cytopathic tissue damage by extrahepatic replication, or immunological processes induced by an overwhelming host immune response, are possible origins of HEV-associated extrahepatic manifestations. Hepatologists should be aware of the possibility that acute or chronically HEV-infected patients could develop extrahepatic manifestations. Neurologists, nephrologists, rheumatologists and other groups of physicians should consider HEV infection as a potential differential diagnosis when observing one of the diseases described in this review. Ribavirin and steroids have been used in small groups of patients with extrahepatic manifestations of HEV, but the efficacy of these drugs still needs to be verified by large, multicenter studies. This article comprehensively reviews the published literature regarding HEV and extrahepatic manifestations. We discuss the probability of specific extrahepatic diseases being caused by previous or ongoing HEV infection, and summarize the published knowledge about antiviral treatment in extrahepatic disorders.

Epidemiology of Hepatitis E Virus in European Countries

Over the last decade the seroprevalence of immunoglobulin (IgG) anti hepatitis E virus (HEV) has been increasing in European countries and shows significant variability among different geographical areas. In this review, we describe the serological data concerning the general population and risk groups in different European countries. Anti-HEV antibody prevalence ranged from 1.3% (blood donors in Italy) to 52% (blood donors in France). Various studies performed on risk groups in Denmark, Moldova and Sweden revealed that swine farmers have a high seroprevalence of HEV IgG (range 13%-51.1%), confirming that pigs represent an important risk factor in HEV infection in humans. Subtypes 3e,f are the main genotypes detected in the European population. Sporadic cases of autochthonous genotype 4 have been described in Spain, France, and Italy. Although most HEV infections are subclinical, in immune-suppressed and transplant patients they could provoke chronic infection. Fulminant hepatitis has rarely been observed and it was related to genotype 3. Interferon and ribavirin treatment was seen to represent the most promising therapy.

Hepatitis E virus antibody prevalence in hunters from a district in Central Germany, 2013: a cross-sectional study providing evidence for the benefit of protective gloves during disembowelling of wild boars

Background

In Germany, 17 % of the general human population have antibodies to hepatitis E virus (HEV) (recomLine HEV-IgG/IgM immunoassay [Mikrogen GmbH]). Wild boars represent an animal reservoir for HEV genotype 3, which is the common genotype in Germany. We estimated the seroprevalence among hunters with contact to wild boars to identify factors that may be associated with past or present HEV infection.

Methods

In 2013, the local veterinarian authority in a district in Central Germany attended meetings of hunters who provided blood specimens and completed a questionnaire collecting information on age, sex, hunting-related activities and consumption of wild boar meat. Specimens of wild boars were taken during drive hunts in this district during the season 2012/2013. All specimens were tested for HEV RNA and anti-HEV IgM and IgG antibodies. Log-binomial regression was used to estimate prevalence ratios (PR) for the hunters.

Results

Of 126 hunters (median age 55; 94 % male) 21 % tested positive for anti-HEV IgG antibodies (95 % confidence interval [CI] 13–28 %) (recomWell HEV IgG assay [Mikrogen GmbH]). Anti-HEV prevalence was highest in the age group of the 70–79-year-olds (67 %; 95 % CI 39–95 %). Wild boars showed an average anti-HEV prevalence of 41 %. HEV RNA was detected in 4/22 (18 %) liver specimens and in 1/22 (4.5 %) muscle specimens. Most wild boars were tested positive for HEV RNA (3/10; 30 %) and HEV-specific antibodies (7/15; 47 %) in the southwestern part of the district. Hunters preferring this hunting ground had a lower anti-HEV prevalence when gloves were frequently used during disembowelling of wild boars compared to hunters using gloves never or infrequently (age-adjusted PR 0.12; 95 % CI 0.02–0.86).

Conclusions

Hunters may benefit from wearing gloves when in contact with blood or body fluids of HEV animal reservoirs. Anti-HEV prevalence among the hunters of this study did not significantly differ from that of the general population suggesting that other factors play a major role in the epidemiology of HEV in Germany.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1199-y) contains supplementary material, which is available to authorized users.

Hepatitis E in hemodialysis and kidney transplant patients in south-east Italy

AIM: To investigate the serovirological prevalence and clinical features of hepatitis E virus (HEV) infection in end-stage renal failure patients and in the healthy population.

METHODS: HEV infection is a viral disease that can cause sporadic and epidemic hepatitis. Previous studies unexpectedly showed a high prevalence of HEV antibodies in immunosuppressed subjects, including hemodialysis (HD) patients and patients who had undergone kidney transplant. A cohort/case-control study was carried out from January 2012 to August 2013 in two hospitals in southern Italy (Foggia and S. Giovanni Rotondo, Apulia). The seroprevalence of HEV was determined in 801 subjects; 231 HD patients, 120 renal transplant recipients, and 450 health individuals. All HD patients and the recipients of renal transplants were attending the Departments of Nephrology and Dialysis at two hospitals located in Southern Italy, and were included progressively in this study. Serum samples were tested for HEV antibodies (IgG/IgM); in the case of positivity they were confirmed by a Western blot assay and were also tested for HEV-RNA, and the HEV genotypes were determined.

RESULTS: A total of 30/801 (3.7%) patients were positive for anti-HEV Ig (IgG and/or IgM) and by Western blot. The healthy population presented with a prevalence of 2.7%, HD patients had a prevalence of 6.0%, and transplant recipients had a prevalence of 3.3%. The overall combined HEV-positive prevalence in the two groups with chronic renal failure was 5.1%. The rates of exposure to HEV (positivity of HEV-IgG/M in the early samples) were lower in the healthy controls, but the difference among the three groups was not statistically significant (P > 0.05). Positivity for anti-HEV/IgM was detected in 4/30 (13.33%) anti-HEV Ig positive individuals, in 2/14 HD patients, in 1/4 transplant individuals, and in 1/12 of the healthy population. The relative risk of being HEV-IgM-positive was significantly higher among transplant recipients compared to the other two groups (OR = 65.4, 95%CI: 7.2-592.7, P < 0.001), but the subjects with HEV-IgM positivity were numerically too few to calculate a significant difference. No patient presented with chronic hepatitis from HEV infection alone.

CONCLUSION: This study indicated a higher, but not significant, circulation of HEV in hemodialysis patients vs the healthy population. Chronic hepatitis due to the HEV virus was not observed.

Epidemiology of hepatitis e virus infection in patients on chronic hemodialysis

Background:

Many studies have been done on the epidemiology of Hepatitis E on general population, but the data among patients with end stage renal disease (ESRD) are few and give conflicting results.

Objectives:

The aim of this study was to investigate the prevalence of hepatitis E virus (HEV) infection and its relationship in ESRD patients undergoing maintenance hemodialysis (HD).

Patients and Methods:

This cross-sectional study was carried out on ESRD patients treated with HD in Imam Khomeini Hospital, Ahvaz city, Southwest of Iran. Blood sampling of patients was collected immediately before the dialysis session and the serum were evaluated for anti-HEV IgG titers by enzyme-linked immunosorbent assays. The statistical package for social sciences (SPSS) version 15 software was used for data analysis.

Results:

Out of 47 ESRD patients, 27 were male (57.4%) and 20 were female (42.6%), with mean age of 55.27 ± 8.1 years. The prevalence of anti-HEV antibody was 10.6 % (five patients, four male and one female). The mean age of HEV positive and negative patients were 58 ± 5.52 and 53.82 ± 15.55 years, respectively without any significant difference (P = 0.058). There also was no significant association between HEV and gender (P = 0.28). The mean time of HD in HEV positive and negative patients were 1224.2 and 1168.5 days, respectively with no significant association (P = 0.88). In addition, there also was no association between HEV and HCV (P = 0.61).

Conclusions:

According to the present study, the prevalence of anti-HEV IgG antibody was 10.63 % among chronic HD patients and there was no association between HEV, age, gender, duration of HD and HCV antibody titer.

Seroprevalence of hepatitis E virus in domestic pigs and wild boars in Switzerland

Hepatitis E is considered an emerging human viral disease in industrialized countries. Studies from Switzerland report a human seroprevalence of hepatitis E virus (HEV) of 2.6-21%, a range lower than in adjacent European countries. The aim of this study was to determine whether HEV seroprevalence in domestic pigs and wild boars is also lower in Switzerland and whether it is increasing and thus indicating that this zoonotic viral infection is emerging. Serum samples collected from 2,001 pigs in 2006 and 2011 and from 303 wild boars from 2008 to 2012 were analysed by ELISA for the presence of HEV-specific antibodies. Overall HEV seroprevalence was 58.1% in domestic pigs and 12.5% in wild boars. Prevalence in domestic pigs was significantly higher in 2006 than in 2011. In conclusion, HEV seroprevalence in domestic pigs and wild boars in Switzerland is comparable with the seroprevalence in other countries and not increasing. Therefore, prevalence of HEV in humans must be related to other factors than prevalence in pigs or wild boars.

Host immune status and response to hepatitis E virus infection

Hepatitis E virus (HEV), identified over 30 years ago, remains a serious threat to life, health, and productivity in developing countries where access to clean water is limited. Recognition that HEV also circulates as a zoonotic and food-borne pathogen in developed countries is more recent. Even without treatment, most cases of HEV-related acute viral hepatitis (with or without jaundice) resolve within 1 to 2 months. However, HEV sometimes leads to acute liver failure, chronic infection, or extrahepatic symptoms. The mechanisms of pathogenesis appear to be substantially immune mediated. This review covers the epidemiology of HEV infection worldwide, the humoral and cellular immune responses to HEV, and the persistence and protection of antibodies produced in response to both natural infection and vaccines. We focus on the contributions of altered immune states (associated with pregnancy, human immunodeficiency virus [HIV], and immunosuppressive agents used in cancer and transplant medicine) to the elevated risks of chronic infection (in immunosuppressed/immunocompromised patients) and acute liver failure and mortality (among pregnant women). We conclude by discussing outstanding questions about the immune response to HEV and interactions with hormones and comorbid conditions. These questions take on heightened importance now that a vaccine is available.

An analysis of the benefit of using HEV genotype 3 antigens in detecting anti-HEV IgG in a European population

Background

The benefit of using serological assays based on HEV genotype 3 in industrialised settings is unclear. We compared the performance of serological kits based on antigens from different HEV genotypes.

Methods

Taking 20 serum samples from patients in southwest France with acute HEV infection (positive PCR for HEV genotype 3) and 550 anonymised samples from blood donors in southwest Switzerland, we tested for anti-HEV IgG using three enzyme immunoassays (EIAs) (MP Diagnostics, Dia.Pro and Fortress) based on genotype 1 and 2 antigens, and one immunodot assay (Mikrogen Diagnostik recomLine HEV IgG/IgM) based on genotype 1 and 3 antigens.

Results

All acute HEV samples and 124/550 blood donor samples were positive with ≥1 assay. Of PCR-confirmed patient samples, 45%, 65%, 95% and 55% were positive with MP Diagnostics, Dia.Pro, Fortress and recomLine, respectively. Of blood donor samples positive with ≥1 assay, 120/124 (97%), were positive with Fortress, 19/124 (15%) were positive with all EIAs and 51/124 (41%) were positive with recomLine. Of 11/20 patient samples positive with recomLine, stronger reactivity for HEV genotype 3 was observed in 1/11(9%), and equal reactivity for both genotypes in 5/11 (45.5%).

Conclusions

Although recomLine contains HEV genotype 3, it has lower sensitivity than Fortress in acute HEV infection and fails to identify infection as being due to this genotype in approximately 45% of patients. In our single blood donor population, we observe wide variations in measured seroprevalence, from 4.2% to 21.8%, depending on the assay used.

Serological investigation for hepatitis E virus infection in the patients with chronic maintenance hemodialysis from southwest of Iran

BACKGROUND AND OBJECTIVES

A global distribution has been shown for hepatitis E virus (HEV) infection. Although the fecal-oral was considered as the primary infection route, there is controversial evidence for increased risk of the infection and consequent problems in patients on maintenance hemodialysis (HD) with suppressed immunity. The aim is to find if the prevalence of anti-HEV IgG, in patients with maintenance HD is higher than normal population in southwest of Iran.

MATERIALS AND METHODS

During November and December 2010, in a cross-sectional study we compared the seroprevalence of HEV among 80 patients with maintenance HD and 276 healthy individuals from Jahrom and Shiraz, Southwest of Iran. In addition to the clinical and laboratory records, serum samples were tested for the presence of IgG anti-HEV antibody by enzyme immunoassay (ELISA) test. The Chi-square, the Student's 't' and Fisher's exact tests were used for the statistical analysis.

RESULTS

ELISA tests detected anti-HEV antibody in five males of the patients (6.3%) and in eight of the healthy controls (2.9%, 6 males and 2 female) which statistically were not different. The mean levels of the aspartate aminotransferase and the alanine aminotransferase in the sera of the patients were 19.96±11.08U/L and 23.93±14.26 IU/L, respectively. However, no one of the individuals with positive anti-HEV antibody showed elevated liver enzymes. Moreover, there was not a significant association between positive anti-HEV antibody result, age and the history of the hemodialysis.

CONCLUSIONS

We did not observe statistically significant higher anti-HEV prevalence among patients with chronic HD; however, more safety precaution is needed to keep HD patients from the risk of possible exposure to HEV infection.

Seroprevalence of fecal-oral transmitted hepatitis A and E virus antibodies in Burkina Faso

Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections occur chiefly as a result of unhygienic conditions. The purpose of this study was to assess the seroprevalence of antibodies to both viruses in central Burkina Faso in the absence of a recorded hepatitis epidemic. Serum samples from 178 blood donors (131 males and 47 females) and from 189 pregnant women were collected from November 2010 to March 2012, at blood banks and medical centers in Burkina Faso. An immunochromatography test was used to screen for Anti-HAV IgM and IgG in a subgroup of 91 blood donors and 100 pregnant women. The seroprevalence of anti-HAV IgG was 14.3% [CI95, 7.1-21.4%] for all blood donors and 23% [CI95, 14.8-31.2%] for pregnant women. Anti-HEV IgG were detected using the ELISA kits Dia.pro and Wantai and were found in 19.1% [CI95, 13.3-24.9%] of the blood donors and 11.6% [CI95, 7.1-16.2%] of the pregnant women. The seroprevalences of anti-HAV and anti-HEV IgGs did not differ significantly between men and women blood donors. Anti-HAV IgM was detected in 3.3% of the blood donors and in 2% of the pregnant women. These findings for asymptomatic individuals indicate that the HAV and HEV circulate at low but significant levels. This is the first evaluation of the acute hepatitis virus burden in Burkina Faso and the underlying epidemiologic status of the population.

Hepatitis E virus seroprevalence among blood donors in southwest Switzerland

AIM

The aim of this study was to determine the seroprevalence of Hepatitis E virus (HEV) among blood donors in southwest Switzerland.

BACKGROUND

HEV is recognized as a food-borne disease in industrialized countries, transmitted mainly through pork meat. Cases of transmission through blood transfusion have also been reported. Recent studies have revealed seroprevalence rates of 13.5%, 16.6% and 20.6% among blood donors in England, France and Denmark, respectively.

METHODS

We analyzed 550 consecutive blood donor samples collected in the region of Lausanne, canton of Vaud, Switzerland, for the presence of anti-HEV IgG, using the MP Diagnostics HEV ELISA kit. For each donor, we documented age, sex and alanine aminotransferase (ALT) value.

RESULTS

The study panel was composed of 332 men (60.4%) and 218 women (39.6%). Overall, anti-HEV IgG was found in 27 of 550 samples (4.9%). The seroprevalence was 5.4% (18/332) in men and 4.1% (9/218) in women. The presence of anti-HEV IgG was not correlated with age, gender or ALT values. However, we observed a peak in seroprevalence of 5.3% in individuals aged 51 to 70 years old.

CONCLUSIONS

Compared with other European countries, HEV seroprevalence among blood donors in southwest Switzerland is low. The low seroprevalence may be explained by the sensitivity of commercial tests used and/or the strict regulation of animal and meat imports. Data regarding HEV prevalence in Swiss livestock are lacking and merit exploration.

Hepatitis E in high-income countries

PURPOSE OF REVIEW

To discuss recent advances in characterising viral Hepatitis E (HEV) in nonendemic regions, with a special focus on epidemiology in high-income countries, different clinical aspects of the disease, possible zoonotic origin of these cases and the improvement of Hepatitis E diagnosis.

RECENT FINDINGS

In high-income countries, most cases of Hepatitis E are acquired locally and not imported from endemic regions. Different genotypes are involved in indigenous cases than those in endemic regions. Particular population groups, such as transplant recipients, can be persistently infected by hepatitis E and develop chronic diseases. Viral hepatitis E is frequently observed in people in animal care occupations. Indeed, HEV has a large animal reservoir and this emerging disease in developed countries has probably a zoonotic origin.

SUMMARY

Recent studies on viral Hepatitis E have shown that the epidemiology of the disease differs between endemic and nonendemic regions. Several lines of evidence suggest that Hepatitis E is more frequent than was suspected and that it has a possible animal origin. Particular attention must be paid to the possible chronic evolution of various forms of the disease. Surveillance of human cases and animal reservoirs must be developed further.

Prevalence of occult hepatitis B virus infection in haemodialysis patients from central Greece

AIM: To assess the hepatitis B virus (HBV)-DNA and the prevalence of occult HBV infection in end-stage renal failure (ESRF) patients from Central Greece.

METHODS: Sera from 366 ESRF patients attending five out of six dialysis units from Central Greece were investigated for HBV-DNA by real-time polymerase chain reaction. Only serum samples with repeatedly detectable HBV-DNA were considered positive. IgG antibodies to hepatitis C virus (anti-HCV) were tested by a third generation enzyme linked immunosorbent assay (ELISA), while IgG antibodies to hepatitis E virus (anti-HEV) were tested by two commercially available ELISAs.

RESULTS: HBV-DNA was detected in 15/366 patients (4.1%) and HBsAg in 20/366 (5.5%). The prevalence of occult HBV infection was 0.9% (3/346 HBsAg-negative patients). Occult HBV was not associated with a specific marker of HBV infection or anti-HCV or anti-HEV reactivity. There was no significant difference in HBV-DNA titres, demographic and biochemical features, between patients with occult HBV infection and those with HBsAg-positive chronic HBV infection.

CONCLUSION: In central Greece, 4% of ESRF patients had detectable HBV-DNA, though in this setting, the prevalence of occult HBV seems to be very low (0.9%).

Transmission routes and risk factors for autochthonous hepatitis E virus infection in Europe: a systematic review

Increasing numbers of non-travel-associated hepatitis E virus (HEV) infections have been reported in Europe in recent years. Our objective was to review the evidence on risk factors and transmission routes of autochthonous HEV infection and hepatitis E in Europe in order to develop recommendations for future research, prevention and control. A systematic literature review was performed to identify all primary reports and studies published during 1998-2008 on hepatitis E in humans and animals in Europe by searching Pubmed, reference lists of major articles and international conference proceedings. Each of the 106 included studies was categorized into one of three evidence levels (EL) based on study design and diagnostic methodology. The evidence was generally weak (73 were assigned to EL1, two to both EL1 and EL2, and 30 to EL2), further compounded by the use of poorly validated serological assays in some studies. Only one case-control study was assigned to EL3. Persons with autochthonous hepatitis E infection were on average older than the general population and predominantly male. There was no evidence for one main transmission route of HEV infection or risk factor for hepatitis E. However, zoonotic transmission seemed likely and person-to-person transmission too inefficient to cause clinical disease. Multiple routes of transmission probably exist and should be further investigated through analytical studies and reliable diagnostic kits. Based on current evidence that points to zoonotic transmission from pigs, thorough cooking of all porcine products, prevention of cross-contamination in the kitchen and improved education for occupationally exposed people (e.g. pig farmers, veterinarians and sewage workers) may help prevent HEV infection. Although evidence for parenteral transmission is limited, it is recommended that a risk assessment is undertaken.

[Seroprevalences of hepatitis A and E infections in Tunisia]

OBJECTIVE

Viral hepatitis A (HAV) and E (HEV) infections are still frequent in many regions of the world, particularly in developing countries where sanitary conditions and socioeconomic level are frequently low. In this work, we have studied seroprevalences of these two infections in Tunisian children, teenagers and young adults.

MATERIAL AND METHODS

The studied population included 3357 individuals from different regions of Tunisia and distributed in three groups 1 (n=1145), 2 (n=707) and 3 (n=1505) with a mean of age of 6.94, 12.84 and 20.71 years, respectively.

RESULTS

Rates of HAV infection prevalence of 84.0, 90.5 and 91.7% were found within groups 1, 2 and 3, respectively. These rates are lower than those previously found in the country; thus, primary infection with HAV in Tunisia is progressively shifting to older ages, which is probably due to the improvement of sanitary conditions. Lower anti-HAV prevalences were found in costal regions as compared to the rest of the country. This difference may be due to the higher socioeconomic level of the population living in costal regions. Antibodies against HEV were assessed in individuals of group 3. A seroprevalence of 4.3% was found which indicates that, despite the absence of epidemics, the virus is circulating among the Tunisian population as sporadic cases.

CONCLUSION

The present work contributes to a better knowledge of HAV and HEV infections in Tunisia and highlights the need of the establishment of a national program for virological surveillance of hepatitis cases and of further studies to monitor changes in the epidemiology of these infections.

High prevalence of anti-hepatitis E virus antibodies in blood donors from South West France

Cases of autochthonous acute hepatitis E occur in most industrialized countries and are frequent in the South West of France. The prevalence of anti-hepatitis E virus (HEV) IgG antibodies in blood donors in this area was determined. A total of 529 samples from rural and urban blood donors were tested. The overall prevalence was 16.6%, 19.1% of rural donors and 14.2% of urban donors had anti-HEV antibodies (P = 0.13). The antibodies were widely distributed among all age groups and the sex ratio of the anti-HEV positive blood donors was 1.12 (P = 0.57). Hunting was the only pastime or profession associated with a high prevalence of anti-HEV antibodies (P = 0.038). The frequency of anti-HEV antibodies in blood donors could reflect active autochthonous transmission in this area of France. As the risk factors for HEV infection in industrialized countries are still unknown, further studies are needed to clarify the epidemiology of HEV infection in the Midi-Pyrénées region.

Community-based seroepidemiological survey of hepatitis E virus infection in Catalonia, Spain

The objective of the study was to investigate the prevalence of immunoglobulin G (IgG) antibodies to hepatitis E virus (HEV) infection in a population sample from Catalonia and to analyze the demographic and clinical variables associated with the presence of these antibodies. A total of 1,280 subjects between 15 and 74 years of age were selected randomly from urban and rural areas. Data for sociodemographic and clinical variables were collected by using a questionnaire. IgG antibodies to HEV were determined by an immunoenzymatic method. The odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for studied variables. Multiple logistic regression analysis was used to determine which variables were independently associated with the prevalence of HEV infection. Anti-HEV antibodies were detected in 96 (7.3%) of the 1,280 samples analyzed. The prevalence of antibodies was greater among males (7.8%) than among women (7%) and increased with age for both sexes, from 3% among subjects 15 to 24 years of age to 12% among subjects >/=65 years of age. Bivariate analysis of the sociodemographic and clinical variables showed an association between the prevalence of hepatitis E virus infection and minor surgery (OR, 1.96; 95% CI, 1.24 to 3.11), abdominal surgery (OR, 1.74; 95% CI, 1.12 to 2.73), and, for women, being uniparous or multiparous (OR, 2.84; 95% CI, 1.19 to 6.79). The multivariate analysis showed an association with minor surgery only (OR, 1.68; 95% CI, 1.03 to 2.70). In conclusion, anti-HEV antibodies were detected in 7.3% of the Catalan population. The seroprevalence of anti-HEV antibodies increased with age and was associated with previous minor surgery.

Seroprevalence of hepatitis E virus (HEV) antibody and the possible association with chronic liver disease: a case-control study in Albania

A case-control study involving 109 in-patients with chronic liver disease and 190 in-patients with no apparent liver disease was conducted to evaluate the seroprevalence of anti-HEV antibodies and the possible association with chronic liver disease. Among cases, the anti-HEV prevalence was 36.6% which increased significantly by age; among controls, the prevalence was 12.1% (P<0.05) and was similar among age groups <60 years. Among cases, aged >50 years (OR 4.0, 95% CI 1.4-11) and the presence of end stage liver disease (ESLD) (OR 4.3, 95% CI 1.4-12.8) were associated independently with anti-HEV positivity. The mean optical density, determined by anti-HEV immunoenzymatic test, was significantly higher among patients with ESLD, compared to the other patients. These results indicate that there is a high seroprevalence of anti-HEV in patients with chronic liver disease and a possible association between HEV infection and/or anti-HEV production and advanced stage chronic liver disease.

HCV-RNA qualitative assay based on transcription mediated amplification improves the detection of hepatitis C virus infection in patients on hemodialysis: results from five hemodialysis units in central Greece

BACKGROUND

End-stage renal disease patients (ESRD) on maintenance hemodialysis (HD) are at increased risk of acquiring hepatitis C virus (HCV) infection. An early and accurate diagnosis of HCV infection is important for the prevention of viral transmission and the management of ESRD patients on HD but conventional ELISA and PCR have often failed to reveal active HCV infection.

OBJECTIVES

This study evaluated the prevalence of HCV infection in ESRD patients from all HD units in central Greece using a sensitive HCV-RNA transcription mediated amplification (TMA) assay and compared its sensitivity with that of anti-HCV ELISA.

STUDY DESIGN

Anti-HCV antibody (third generation ELISA), HCV-RNA (TMA) and HCV genotypes (HCV TMA-LiPA) were determined in 366 ESRD Greek patients.

RESULTS

In total, 132 (36%) ESRD patients were HCV positive by ELISA or TMA; 44 by TMA alone, 16 by ELISA alone and 72 positive by both assays. More than half of the viraemic patients had genotype 3a.

CONCLUSIONS

HCV-RNA (TMA) assay appears to increase the accuracy in the diagnosis of HCV infection in HD patients compared to the anti-HCV ELISA and could serve as an additional screening tool in these patients.

Markers of hepatitis viruses and human T-lymphotropic virus types I/II in patients who have undergone open-heart surgery: evidence of increased risk for exposure to HBV and HEV

BACKGROUND

Open-heart procedure is characterized by a high-risk for contracting blood-borne infections. We evaluated the prevalence of several markers of hepatitis viruses (B-E) and human T-cell lymphotropic virus types I/II (HTLV-I/II) in a consecutive series of patients who had undergone open-heart surgery.

METHODS

204 patients and 158 selected age- and sex-matched healthy volunteers were investigated. Samples were collected at least 6-12 months postoperatively. Commercial enzyme immunoassays and confirmatory immunoblot assays for HCV, HEV and HTLV-I/II were used.

RESULTS

None of the subjects tested positive for antibodies to HTLV-I/II. Prevalence of markers of past HBV infection and antibodies to HEV (anti-HEV) were higher in patients than in healthy controls (anti-HBc: 45.1% vs. 31%, p=0.009; anti-HBs: 31.9% vs. 22.2%, p=0.02; anti-HBe: 32.4% vs. 10.1%, p=0.000; anti-HEV: 5.4% vs. 0%, p=0.008). HBsAg and antibodies to HCV did not differ between the groups.

CONCLUSIONS

HTLV, HBsAg and HCV infection markers did not differ between patients and healthy controls. However, patients had significantly increased prevalence of markers of previous HBV infection suggesting that an intensive vaccination schedule against HBV preoperatively might be helpful in minimizing the risk. The increased prevalence of anti-HEV in cardiac patients requires further investigation. Prospective studies are needed in order to definitely address whether the high prevalence of exposure to HBV and HEV infections in patients who had undergone open-heart surgery is procedure-related or not and whether it has any impact on morbidity of these patients.

Acute hepatitis and renal function impairment related to infection by hepatitis E virus in a renal allograft recipient

Clinicians often are faced with an increase in liver enzyme levels. In the majority of cases, the cause is found rapidly. Conversely, in a few cases, the etiologic agent remains unknown and requires either liver biopsy or drug-medication modification. We report a case of acute icteric hepatitis associated with renal function impairment related to infection caused by primary hepatitis E virus (HEV) in a renal transplant recipient who lived in a nonclassic endemic area and had not traveled abroad. Clinicians must be aware that in cases of unexplained hepatitis in organ transplant recipients and in the absence of evident drug hepatotoxicity, HEV should be considered as an etiologic agent for hepatitis. Subsequently, HEV serological tests should be performed, HEV RNA should be looked for in acute-phase serum and stool samples, and liver parameters should be monitored closely because HEV might be responsible, in some cases, for fulminant hepatitis.

Hepatitis E virus infection in hemodialysis patients: a seroepidemiological survey in Iran

BACKGROUND

The hepatitis E virus (HEV) has a global distribution and is known to have caused large waterborne epidemics of icteric hepatitis. Transmission is generally via the fecal-oral route. Some reports have suggested parenteral transmission of HEV. Anti-HEV prevalence data among chronic hemodialysis (HD) patients are few and give conflicting results.

METHODS

This cross-sectional study was conducted in August of 2004. We tested 324 chronic HD patients attending three different units in the city of Tabriz, northwestern part of Iran, for anti-HEV antibody. A specific solid- phase enzyme-linked immunoassay (Diapro, Italy) was used.

RESULTS

The overall seroprevalence of hepatitis E was 7.4 %(95% CI: 4.6%-10.6%). The prevalence rate of HBV and HCV infection were 4.6% (95% CI: 2.3%-6.9%) and 20.4% (95% CI: 16%-24.8%), respectively. No significant association was found between anti-HEV positivity and age, sex, duration of hemodialysis, positivity for hepatitis B or C virus infection markers and history of transfusion.

CONCLUSION

We observed high anti-HEV antibody prevalence; there was no association between HEV and blood borne infections (HBV, HCV, and HIV) in our HD patients. This is the first report concerning seroepidemiology of HEV infection in a large group of chronic HD individuals in Iran.

Hepatitis E virus antibodies in hemodialysis patients: an epidemiological survey in central Greece

Hepatitis E virus (HEV) is the causative agent for enteric non-A, non-B hepatitis. Transmission is mainly via the fecal-oral route but the possibility of an additional parenteric transmission has been raised. Patients undergoing chronic hemodialysis (HD) have an increased risk of exposure to blood transmitted agents. Previous studies concerning prevalence of antibodies to HEV (anti-HEV) among HD patients gave conflicting results. The aim of the study presented here was to determine the prevalence of anti-HEV among HD patients of a well-defined semi-rural region in central Greece (Thessalia region). All patients (n=351, 234 males, mean age 60+/-14 years) who were being treated in the HD units of central Greece (n=5) during 2001 were tested for anti-HEV antibody. Two commercially available specific solid-phase enzyme-linked immunoassays were applied for anti-HEV detection. Hepatitis B virus markers, antibodies to HCV, HIV and HTLV were also screened in all patients by commercially available assays. Serum aminotransferase (AST, ALT) levels were measured by spectrophotometry. 17 anti-HEV-positive patients were found and prevalence was 4.8%, varying from 1.8 - 9.8% in the various HD units. Prevalence of HBsAg and anti-HCV was 5.7% (2.9 - 15%) and 23.6% (11.5 - 36.2%) respectively. The anti-HEV prevalence was increased compared to healthy blood donors in Greece (0.26%, p < 0.01). The highest prevalence of anti-HEV was seen at the HD unit of the General Hospital of Karditsa (9.8%). Risk factors for anti-HEV antibody were not identified: no association was found between anti-HEV positivity and age or sex, duration of HD, hepatitis B or C virus infection markers, previously elevated aminotransferase levels or history of transfusion. Our investigation of HEV infection in the cohort of HD patients in central Greece showed that the prevalence of anti-HEV was greater than in healthy blood donors. There was no association to blood borne infections (HBV, HCV). The high prevalence of anti-HEV we found in one HD unit was probably related to a local infection in the past. However, long-term prospective studies are needed in an attempt to identify whether intra-unit factors are also responsible for the increased prevalence of serologic markers of HEV infection among HD patients.

Prevalence of Antibody to Hepatitis E Virus among Haemodialysis Patients in Taiwan: Possible Infection by Blood Transfusion

BACKGROUND/AIMS

A higher prevalence of anti-hepatitis E virus (HEV) in non-endemic viral hepatitis such as in Germany has been reported in our previous study. The aim of this study was to assess the seroepidemiology of HEV among haemodialysis (HD) patients in Shin-Kong Hospital, Taiwan, and to evaluate whether there was an increased risk of infection and exposure to HEV even in an area of endemic viral hepatitis.

METHODS

Serum samples obtained from 400 Taiwanese patients on chronic HD (group 1), 400 sex- and age-matched healthy subjects (group 2) and hospital patients (group 3) were tested for the IgG anti-HEV.

RESULTS

The prevalence of anti-HEV among the HD patients and the healthy controls were 31 and 8.9%, respectively. The difference (22%) was statistically significant (p < 0.01). In comparison, the anti-HEV in hospital patients was 16%.

CONCLUSION

The study indicated a significantly higher risk of HEV infection among patients on chronic HD in endemic regions of viral hepatitis such as Taiwan. Mostly because of anaemia, HD patients usually received packed transfusion (red blood cells) if their haemoglobin was low. It is possible that HEV infection may be transmitted through blood transfusions in an endemic area. In such areas, appropriate strategies should be adopted to prevent the risk of HEV among HD patients.

Low prevalence of HCV, HIV, and HTLV-I/II infection markers in northwestern Greece: results of a 3-year prospective donor study (1995-1997)

Background: The risk of infection with transfusion-transmitted viruses has been reduced remarkably. A zero-risk blood supply, however, remains a popular goal. A 3-year prospective donor study was conducted in the Epirus region of Greece to determine the prevalence of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis B virus, and hepatitis C virus (HCV). Herein, we report the prevalence of HIV, HTLV, and HCV infection markers in this area. Methodology: Between January 1, 1995 and December 31, 1997, 6696 donors were investigated for the presence of anti-HIV, anti-HTLV, and anti-HCV antibodies using standard enzyme immunoassays (EIA). Every sample with anti-HCV reactivity by third-generation EIA was further investigated using a third-generation recombinant immunoblot assay (RIBA 3.0) and HCV-RNA by a combination of polymerase chain reaction (PCR) and DNA EIA. Results: None of the donors tested positive for anti-HIV or anti-HTLV antibodies. In contrast, anti-HCV was detected in 41 donors (0.61%). Using a RIBA 3.0 test, eight donors tested positive and eight had indeterminate results, while 25 tested negative. Seven of the eight donors with both EIA and RIBA 3.0 reactivity had increased levels of aminotransferases and detectable serum HCV-RNA. The remaining 34 donors had repeatedly normal aminotransferases and three times negative HCV-RNA. Liver biopsy was performed in anti-HCV/HCV-RNA-positive donors (7/41). The lesions were compatible with chronic hepatitis C in all of them. Conclusion: A zero prevalence of HIV and HTLV infection markers was found. Although the number of annual donations in this study was relatively low, the negative data for HIV and HTLV clearly indicate that rates of these infections are low in our region and that infected donors will be seen infrequently. HCV infection in blood donors remains very low in our region and is similar to the data reported in other industrialized countries. In fact, the prevalence of definite HCV infection seems to be very low (7/6696; 0.1%). However, a significant proportion of anti-HCV-reactive donors by third-generation EIA (33/41) had indeterminate or negative results by the RIBA 3.0. The latter donors were repeatedly negative for HCV-RNA. This finding may indicate that some donors tested false-positive for anti-HCV, although the possibility of true HCV infection contracted in the distant past cannot be excluded. In our opinion, close attention to mandatory principles of transfusion medicine, along with the screening of plasma donors using nucleic acid amplification technology, are the only methods that can further ensure the safety of our blood supply.

Prevalence of hepatitis virus infections in Kosovar refugees

OBJECTIVES

To assess the prevalence of viral hepatitis infections in a sample of Kosovar refugees having arrived in southern Italy as a result of the 1999 war in the Balkans.

METHODS

The 526 subjects who enrolled on voluntary basis from all age groups were tested for the prevalence of serologic markers for hepatitis virus types A, B, C, D, and E (HAV, HBV, HCV, HDV, HEV).

RESULTS

Among the 526 refugees, the prevalence of total anti-HAV antibodies was 81%. A relevant finding was the presence of total anti-HAV antibodies in 61% of the children up to 10 years of age. The prevalence of anti-HEV antibodies was 2.5% among the subjects. Fifteen subjects (2.9%) were positive for hepatitis B surface antigen (HBsAg), whereas 17.5% tested positive for anti-hepatitis B core antigen (anti-HBc). In children up to 10 years of age, the prevalence of HBsAg and anti-HBc was found to be 0.4% and 6%, respectively. In subjects aged 11 to 20 years, 4.2% tested positive for HBsAg and 20.2% for anti-HBc. In the age group 21 to 30 years, 7.1% of the subjects were found to be HBsAg carriers, whereas 25.9% were found to be positive for anti-HBc. Among the refugees over 30 years of age, the prevalence of HBsAg was 4.2%, whereas anti-HBc was 43.7%. None of the refugees tested positive for anti-HDV. The prevalence of anti-HCV antibodies was 0.7%.

CONCLUSIONS

The results of this seroepidemiologic study indicate a high circulation of HAV in the Kosovar population, whereas the prevalence of HEV antibodies was low and comparable to that of other European countries. The HBV infection seems to be at an intermediate level of endemicity and an immunization policy against HBV infection, through vaccination of all newborns and children before adolescence, may be advisable. Results of this study indicate that the level of endemicity of HCV infection in the Kosovar population is low.

Hepatitis E virus infection in haemodialysis patients: a case-control study in Saudi Arabia

To determine the prevalence of antibody to hepatitis E virus (IgM anti-HEV) among haemodialysis patients and evaluate whether there was an increased risk of infection and exposure to HEV in an area of endemic viral hepatitis, serum samples obtained from 83 Saudi patients on chronic haemodialysis (group 1), 400 sex- and age-matched healthy subjects (group 2) and hospital patients (group 3) were tested for the IgM anti-HEV and IgG anti-HEV. The prevalence of anti-HEV among the patients (group 1) and the healthy controls were 4.8% and 0.3%, respectively. The difference (4.5%) was statistically significant, with a calculated odds ratio (OR) of 20.2 (95% CI = 2.1-481.0; P = 0.0002). In contrast, there was no significant difference in the prevalence rates of IgG anti-HEV (7.2% vs 10.8%) in both groups. In nonhaemodialysis patients with various diseases, 1.6% (1 of 64) of outpatients (group 3) and none (0 of 113) of the ward patients (group 4) was positive for IgM anti-HEV. Thus, the prevalence (4 of 83) of IgM anti-HEV in the haemodialysis patients was significantly higher than the rate (1 of 177) in the combined groups of nonhaemodialysis hospital patients. The calculated OR was 8.9 (95% CI = 0.92, 212.8; P = 0.037). IgM antibody to hepatitis A virus (IgM anti-HAV) was not detected in any subjects, and the prevalence rates of IgG anti-HAV were similar in the patients and controls (72.3% and 74.3% in groups 1 and 2, respectively, and 75.7% combined groups 3 and 4). The study indicated a significantly higher risk of acute HEV infection among patients on chronic haemodialysis. It is possible that these were nosocomial infections acquired by person-to-person transmission in the haemodialysis unit. However, it is more probable that the infections were community acquired, a conclusion supported albeit indirectly by the lack of a significant difference between the prevalence in haemodialysis patients (4.8%) and outpatients (1.6%). In areas of endemic HEV, appropriate strategies should be adopted to prevent the risk of HEV among haemodialysis patients.

Cryoglobulinemia due to chronic viral hepatitis infections is not a major problem in clinical practice

Background: Essential mixed cryoglobulinemia (EMC) is a systemic disease frequently associated with chronic viral hepatitis. This study was conducted in order to assess the prevalence of EMC in patients with hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. We also evaluated the possible associations of EMC with (1) the clinical, virological, and histological status of liver disease; (2) the presence of EMC-related symptoms; and (3) the response rate to interferon-alpha (IFN-alpha) treatment, in an attempt to address whether EMC is a major problem in hepatitis patients. Methodology: A total of 154 consecutive patients (104 with HBV and 50 with HCV infection) were investigated for the presence of rheumatoid factor (RF), cryoglobulins, and EMC-related manifestations. Sixty-two HBV patients were chronic carriers of hepatitis B surface antigen, 29 had chronic hepatitis B, and 13 HBV cirrhosis. Thirty-five HCV patients had chronic hepatitis C and 15 HCV cirrhosis. HCV genotyping was performed in 44 patients. Results: The prevalence of cryoglobulins was significantly higher (P<0.001) in HCV patients (46%) than in HBV patients (13.4%). EMC was associated with a high frequency of RF detection, older age, and longer duration of viral diseases. Weakness or malaise, arthralgias, and purpura were significantly more frequent in cryoglobulin-positive patients. These manifestations, however, were mild in most of the patients. The EMC-related symptoms were significantly associated with the presence of HCV infection, increased levels of cryoglobulins, and RF detection (P<0.01, P<0.05, and P<0.000005, respectively). Worse liver histology was unrelated to a higher prevalence or increased levels of cryoglobulins in both HBV and HCV infection. There was no relationship between EMC and a specific HCV genotype. IFN-alpha therapy led to the disappearance of cryoglobulins and EMC-related manifestations in most cases. The response rate to IFN-alpha was similar in both groups of patients (with and without EMC). Conclusions: A higher prevalence of EMC was observed in HCV patients than in HBV patients. However, this finding was unrelated to overt clinical manifestations of EMC, a specific HCV genotype, or worse liver histology. The latter suggests that EMC does not contribute to liver injury and vice versa, that EMC pathogenesis is rather unrelated to the degree of liver injury. From a clinical point of view, testing for cryoglobulins seems reasonable only for HCV patients with EMC-related manifestations, since this may have therapeutic consequences. RF detection could be used primarily as a surrogate marker for the existence of cryoglobulins.

Value of anti-HBc screening of blood donors for prevention of HBV infection: results of a 3-year prospective study in Northwestern Greece

BACKGROUND

The risk of infection with transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply remains a popular goal. Some authorities have introduced the screening for antibody to HBc (anti-HBc) as a surrogate test for the presence of several infectious agents. A 3-year prospective study was conducted in the Epirus region of Greece to determine the prevalence of several blood-borne viruses. One component of the study was the prevalence of HBV infection markers and the potential value of anti-HBc testing of donors in this area.

STUDY DESIGN AND METHODS

Between January 1, 1995, and December 31, 1997, some 6696 donors were investigated for the presence of HBV infection markers by standard EIAS: Every sample that tested HBsAg-negative but anti-HBc-reactive alone or in combination with either or both antibodies to HBV e antigen (anti-HBe) and low-titered antibodies to HBsAg (anti-HBs <20 mIU/mL) was further investigated for the presence of HBV DNA by a combination of PCR and DNA EIA.

RESULTS

Of these 6696 donors, 15.8 percent tested positive for at least one serologic marker of HBV infection (HBsAg prevalence, 0.85%). Anti-HBc reactivity alone or in combination with either or both anti-HBe and low-titered anti-HBs was found in 282 donors (4.2%). None tested HBV-DNA positive. No transfusion-associated HBV infections were recorded in the recipients of the above 282 blood units.

CONCLUSION

A moderate prevalence of HBV infection markers was found. However, taking into account previous studies from this region, it appears that the HBsAg prevalence has declined. In addition, the present study cannot recommend the introduction of anti-HBc screening as a surrogate marker of occult HBV infection. The adoption of this exclusion criterion in this region would result in unacceptably high rejection rates among otherwise healthy donors. The absence of any case of transfusion-associated HBV infection after the transfusion of all HBsAg-negative, anti-HBc-positive units appears to provide further support for the negative HBV DNA results. Before a consideration of screening donors, efforts must be focused on reducing the number of false-positive anti-HBc results.

A review of hepatitis E virus

Hepatitis E virus (HEV) is a major cause of outbreaks and sporadic cases of viral hepatitis in tropical and subtropical countries but is infrequent in industrialized countries. The virus is transmitted by the fecal-oral route with fecally contaminated drinking water being the usual vehicle. Hepatitis resulting from HEV infection is a moderately severe jaundice that is self-limiting in most patients. Young adults, 15 to 30 years of age, are the main targets of infection, and the overall death rate is 0.5 to 3.0%. However, the death rate during pregnancy approaches 15 to 25%. Death of the mother and fetus, abortion, premature delivery, or death of a live-born baby soon after birth are common complications of hepatitis E infection during pregnancy. Hepatitis E virus is found in both wild and domestic animals; thus, HEV is a zoonotic virus. The viruses isolated from swine in the United States or Taiwan are closely related to human HEV found in those areas. The close genetic relationship of the swine and human virus suggests that swine may be a reservoir of HEV. In areas where swine are raised, swine manure could be a source of HEV contamination of irrigation water or coastal waters with concomitant contamination of produce or shellfish. Increasing globalization of food markets by industrialized countries has the potential of introducing HEV into new areas of the world. The purpose of this review is to cover certain aspects of hepatitis E including the causative agent, the disease, diagnosis, viral detection, viral transmission, epidemiology, populations targeted by HEV, and the role of animals as potential vectors of the virus.