High prevalence of hepatitis E antibodies among Danish prisoners and drug users

Serological and molecular survey of rat hepatitis E virus (Rocahepevirus ratti) in drug users

ABSTRACTRat hepatitis E virus (ratHEV) is an emerging cause of acute hepatitis of zoonotic origin. Since seroprevalence studies are scarce, at-risk groups are almost unknown. Because blood-borne infections frequently occur in people with drug use, who are particularly vulnerable to infection due to lack of housing and homelessness, this population constitutes a priority in which ratHEV infection should be evaluated. Therefore, the aim of this study was to evaluate the ratHEV seroprevalence and RNA detection rate in drug users as a potential at-risk population. We designed a retrospective study involving individuals that attended drug rehabilitation centres. Exposure to ratHEV was assessed by specific antibody detection using ELISA and dot blot (DB) assay and the presence of active infection by ratHEV RNA detection using RT-qPCR. Three-hundred and forty-one individuals were included, the most of them being men (67.7%) with an average age of 45 years. A total of 17 individuals showed specific IgG antibodies against ratHEV (4.6%; 95% CI; 3.1%-7.9%). One case of active ratHEV infection was identified (0.3%; 95% CI: 0.1%-1.8%). This was a 57-year-old homeless woman with limited financial resources, who had active cocaine and heroin use via parenteral route. In conclusion, we identified a potential exposure to ratHEV among drug users. Targeted studies in drug users with proper control groups are necessary to evaluate high-risk populations and transmission routes more accurately.

Risk of Hepatitis E among Persons Who Inject Drugs in Hong Kong: A Qualitative and Quantitative Serological Analysis

Hepatitis E virus (HEV) is an important cause of hepatitis, which can be transmitted via the bloodborne route. However, risk of hepatitis E among persons who inject drugs (PWIDs) is poorly understood. This study aimed to elucidate whether PWIDs are at risk for hepatitis E. We performed HEV IgM, IgG and nucleic acid detection on a cohort of 91 PWIDs and 91 age- and sex-matched organ donors. Blood HEV IgG was measured using the WHO HEV antibody standard. The effects of age, gender and addictive injection use on HEV serostatus and concentration were assessed. HEV IgG seroprevalence was 42/91 (46.2%) in the PWID group and 20/91 (22%) in the donor group (odds ratio = 3.04 (1.59–5.79), p = 0.0006). The median HEV IgG concentration was 5.8 U/mL (IQR: 2.5–7.9) in the PWID group and 2.1 U/mL (IQR: 1.2–5.3) in the donor group (p = 0.005). Increasing age and addictive injection use were significantly associated with HEV IgG serostatus, but only addictive injection use was associated with HEV IgG concentration (p = 0.024). We conclude that PWIDs are at increased risk for hepatitis E and are prone to repeated HEV exposure and reinfection as indicated by higher HEV IgG concentrations.

The Prevalence of Hepatitis E in a Patient Cohort Presenting With Addictive Injection Behavior

Introduction: Hepatitis E is the most common cause of acute viral hepatitis worldwide. Seroprevalence is approximately 15% in developed countries, and 22% in France. hepatitis E virus (HEV) can be transmitted via transfusions and therefore possibly intravenous (IV) drug use. Hepatitis E serology is routinely tested in patients who seek medical advice for addictive injection behavior at the addiction treatment, support and prevention unit of Toulouse University Hospital. We assume that hepatitis E is more prevalent in patients presenting with addictive injection behavior than in the general French population. Methods: Hepatitis E serological assays [immunoglobulin M (IgM) and IgG] were carried out for all patients presenting with addictive injection behavior during an initial evaluation. The controls were taken from a cohort of 3,353 blood donors living in southern France and who donated blood during the first 2 weeks of October 2011. Results: We included 52 patients presenting with addictive injection behavior and 103 healthy controls matched for age, sex, and area of residence. We found no difference between patients and controls for the prevalence of hepatitis E: patients vs. healthy controls: positive IgGs: 42.31%, 95% confidence interval (CI) (28.73-56.80%) vs. 43.43%, 95% CI (33.50-53.77%) (p = 0.89) and positive IgMs: 3.85%, 95% CI (0.47-13.22%) vs. 4.85%, 95% CI (0.16-10.97%) (p = 0.57). Conclusion: There was no difference in HEV seroprevalence between IV drug users and the general population, suggesting that the IV route of HEV infection is not significant in this population.

Hepatitis E virus seroprevalence and determinants in various study populations in the Netherlands

BACKGROUND

The epidemiology of hepatitis E virus (HEV) is not fully understood. In this study, we assessed putative risk factors for HEV seropositivity in various study populations in the Netherlands.

METHODS

Data and samples from five different study populations were analysed: (A) blood donors (n = 5,239), (B) adults reporting a vegetarian life style since the age of 12 years (n = 231), (C) residents of Amsterdam, the Netherlands, with different ethnic backgrounds (n = 1,198), (D) men who have sex with men (MSM) (HIV positive and HIV negative) (n = 197), and (E) persons who use drugs (PWUD) (HIV positive and HIV negative) (n = 200). Anti-HEV immunoglobulin M (IgM) and immunoglobulin G (IgG) testing was performed using ELISA test (Wantai).

RESULTS

HEV IgM seroprevalence was low across all study populations (<1% to 8%). The age and gender-adjusted HEV IgG seroprevalence was 24% among blood donors (reference group) and 9% among the vegetarian group (adjusted Relative Risk [aRR]:0.36, 95%CI:0.23-0.57). Among participants of different ethnic backgrounds, the adjusted HEV IgG seroprevalence was 16% among participants with a Dutch origin (aRR:0.64, 95%CI:0.40-1.02), 2% among South-Asian Surinamese (aRR:0.07, 95%CI:0.02-0.29), 3% among African Surinamese (aRR:0.11, 95%CI:0.04-0.34), 34% among Ghanaian (aRR:1.53, 95%CI:1.15-2.03), 19% among Moroccan (aRR:0.75, 95%CI:0.49-1.14), and 5% among Turkish (aRR:0.18, 95%CI:0.08-0.44) origin participants. First generation Moroccans had a higher risk for being IgG HEV seropositive compared to second generation Moroccan migrants. The statistical power to perform these analyses in the other ethnic groups was too low. In the MSM group the IgG HEV seroprevalence was 24% (aRR:0.99, 95%CI:0.76-1.29), and among PWUD it was 28% (aRR:1.19, 95%CI:0.90-1.58). The number of sexual partners in the preceding six months was not significantly associated with IgG HEV seropositivity in MSM. The association between HIV status and HEV seropositivity was significant in PWUD, yet absent in MSM. HIV viral load and CD4 cell count were not associated with HEV seropositivity in HIV positive MSM and PWUD.

CONCLUSIONS

Vegetarians were significantly less often HEV seropositive. Ethnic origin influenced the risk for being IgG HEV seropositive. MSM and PWUD were not at higher risk for being IgG HEV seropositive than blood donors.

Hepatitis E in High-Income Countries: What Do We Know? And What Are the Knowledge Gaps?

Hepatitis E virus (HEV) is a positive-strand RNA virus transmitted by the fecal–oral route. HEV genotypes 1 and 2 infect only humans and cause mainly waterborne outbreaks. HEV genotypes 3 and 4 are widely represented in the animal kingdom, and are mainly transmitted as a zoonosis. For the past 20 years, HEV infection has been considered an imported disease in developed countries, but now there is evidence that HEV is an underrecognized pathogen in high-income countries, and that the incidence of confirmed cases has been steadily increasing over the last decade. In this review, we describe current knowledge about the molecular biology of HEV, its clinical features, its main routes of transmission, and possible therapeutic strategies in developed countries.

Hepatitis E virus infection in different groups of Estonian patients and people who inject drugs

BACKGROUND

Previously we demonstrated a high prevalence of hepatitis E virus (HEV) in domestic pigs and wild boars, the main reservoir and possible source of HEV infections in humans. But so far there are no reports about spread of HEV in Estonian human population.

OBJECTIVES

The present study aimed to determine the prevalence and genotyping of HEV in different groups of the Estonian adult population.

STUDY DESIGN

Totally 1426 human serum samples were tested (763 patients with clinically diagnosed nonA/B/C hepatitis, 176 hemodialysis patients, 282 patients with suspected HEV infection and 205 people who injected drugs (PWID)). Presence of anti-HEVantibodies was assessed by ELISA and confirmed by immunoblotting. All anti-HEV positive sera were analyzed for RNA by qPCR. Amplified ORF2 region was sequenced and used for phylogenetic analysis.

RESULTS

Antibody assay revealed 49 samples from 1426 (3.4%) with acute (17) or past (32) HEV infection. HEV RNA was detected in 10 anti-HEV IgM positive samples, including 9 samples from patients with suspected HEV infection and 1 hemodialysis patient. Anti-HEV IgG were found in 7.8% patients with suspected HEV infection, in 4% hemodialysis patients, in 2.4% PWID and in 1.96% patients with nonA/B/C hepatitis. All groups demonstrated a trend to share of anti-HEV seroprevalence increasing with age. Phylogenetic analysis of 9 HEV RNA sequences revealed that 3 sequences belonged to HEV genotype 1; 6 ones to genotype 3 (1 sequence belonged to sub-genotype 3a, two ones - sub-genotype 3e, and three ones - to sub-genotype 3f).

CONCLUSIONS

Despite the high seroprevalence among domestic pigs, no evidence of HEV transmission from Estonian pigs to humans was found. The results of our study suggest that HEV infections in Estonia are most likely associated with travel or with consumption of imported food products.

Low prevalence of hepatitis E in Iceland: a seroepidemiological study

OBJECTIVE

Hepatitis E virus (HEV) infection has been reported to be more prevalent in the developed countries than previously thought. HEV infection is an important differential diagnosis in patients with drug-induced liver injury (DILI). The prevalence of hepatitis E was investigated in the general population of Iceland, among pig farmers and patients with DILI.

MATERIALS AND METHODS

Serum samples were tested for hepatitis E IgG, with two commercial ELISA tests: Diagnostic Bioprobes Srl. (Dia Pro) and the Wantai HEV IgG and subjects repeatedly reactive were tested with an immunoblot assay (RecomLINE). Three groups were tested: (1) healthy volunteers (HV), (2) pig farm workers (PFWs) and (3) patients participating in a nationwide prospective study on DILI.

RESULTS

Overall 291 individuals were tested, HV (n = 195), PFW (n = 21) and DILI (n = 75). Only 6/291 (2.1%) tested positive for IgG antibodies to HEV in all three tests. Three HV were HEV IgG antibody positive and three in the DILI group. One PFW tested positive in the Dia Pro and Wantai tests but not in the immunoblot assay. All but one of the positive individuals in all three tests was either of foreign national origin or had spent extended period of time outside of Iceland.

CONCLUSIONS

The seroprevalence of hepatitis E appears to be lower in Iceland than majority of recent studies in other western countries have demonstrated. This may be due to relative isolation and severe restriction on import of livestock from other countries.

Hepatitis E prevalence in a sexual high-risk population compared to the general population

Transmission routes of the hepatitis E virus (HEV) are under debate. Here, we studied possible sexual transmission by comparing HEV prevalence in a Dutch sexual high-risk population (n = 1,482) with that in a general population (n = 1,487) while assessing sociodemographic and sexual risk factors. Overall prevalence of anti-HEV IgG of 18.9% (n = 562) was, adjusting for confounders, similar between the two populations (p = 0.44). Prevalence was higher with each year's increase in age (adjusted OR: 1.03, 95%CI: 1.02-1.04, p<0.01), among men (adjusted OR: 1.24, 95%CI: 1.02-1.50, p = 0.03) and among individuals diagnosed with sexually transmitted infections (adjusted OR: 1.60, 95%CI: 1.02-2.49, p = 0.04). Our results only hint at the possibility of a sexual transmission route for HEV given higher rates in those with chlamydia and/or gonorrheal infections. Sexual transmission is not a dominant transmission route, as its prevalence was not higher for the sexual high-risk population than for the general population.

Risk Factors Associated with Blood Exposure for Sporadic Hepatitis E in Dhaka, Bangladesh

Fecal contamination of drinking water is associated with large hepatitis E virus (HEV) outbreaks of genotypes 1 and 2 in endemic areas. Sporadic transmission of HEV genotypes 3 and 4 in high-income countries has been associated with exposure to blood and animal contact. The objective of the study was to identify the risk factors for hepatitis E and the genotype(s) causing sporadic hepatitis E in Dhaka, Bangladesh. We selected, from a diagnostic center in Dhaka between November 2008 and November 2009, cases presenting with jaundice and anti-HEV IgM antibodies and age-matched controls were defined as those with no history of jaundice and normal blood test results. Serum samples were tested for HEV RNA using real-time reverse transcriptase polymerase chain reaction followed by a sequencing and phylogenetic analysis. A total of 109 cases and 109 controls were enrolled. The cases were more likely to be male (adjusted matched odds ratios [mOR] 2.2, 95% CI: 1.2-3.9; P = 0.01), or have reported contact with another person's blood or blood product, or contact with blood-contaminated sharp instruments (adjusted mOR 2.1, 95% CI: 1.1-4.1; P = 0.03) than controls. There were no significant differences between the cases and the controls in terms of reported high-risk sexual intercourse, consumption of undercooked meat, or contact or drinking fecally-contaminated water. The sera from three cases carried HEV RNA, all belonging to genotype 1. Findings from this study suggest that contact with human blood and sharing sharp instruments may transmit sporadic hepatitis E in Dhaka, Bangladesh. Efforts to prevent the transmission of blood-borne pathogens may also prevent sporadic HEV transmission in this endemic setting.

High seroprevalence against hepatitis E virus in patients with chronic hepatitis C virus infection

BACKGROUND

Hepatitis E virus (HEV) genotype 3 is endemic in Europe. Superinfection with HEV in patients with underlying chronic liver disease can cause hepatic decompensation leading to increased morbidity and mortality.

OBJECTIVES

The prevalence of anti-HEV antibodies was investigated in 204 patients with chronic hepatitis C virus (HCV) infection and different stages of fibrosis.

STUDY DESIGN

Sera were analyzed for anti-HEV IgG, IgM and HEV RNA.

RESULTS

The median age of the patients was 55 years (IQR 40-62 years); 126 (62%) were men. Ninety-eight (48%) patients had a METAVIR fibrosis stage F2 or higher. The prevalence of anti-HEV IgG was 30% (62/204), which was significantly higher than among Swedish blood donors (17%, p<0.01). The prevalence of anti-HEV antibodies was associated with higher age (OR 1.08 (1.05-1.11); p<0.01). It was also higher for patients with a prior history of blood transfusion (48%) as compared to intravenous drug use (IDU; 26%) as the risk factor for acquisition of the HCV infection (OR 2.72 (1.2-6.19); p<0.02). The prevalence of anti-HEV IgG was also significantly higher in patients with significant fibrosis, i.e. ≥F2 (38%; OR 2.04 (1.11-3.76); p=0.02) and/or neoplasm (72%; OR 7.27 (2.46-21.44); p<0.01).

CONCLUSIONS

When adjusted for age, the prevalence of anti-HEV antibodies was significantly higher in patients with previous or current malignant liver disease compared to blood donors. The lack of significant correlation between HCV and HEV infections indicate low level of transmission of HEV by IDU. HEV infections warrant more attention, especially in patients with preexisting liver disease.

Transmission of Hepatitis E Virus in Developing Countries

Hepatitis E virus (HEV), an RNA virus of the Hepeviridae family, has marked heterogeneity. While all five HEV genotypes can cause human infections, genotypes HEV-1 and -2 infect humans alone, genotypes HEV-3 and -4 primarily infect pigs, boars and deer, and genotype HEV-7 primarily infects dromedaries. The global distribution of HEV has distinct epidemiological patterns based on ecology and socioeconomic factors. In resource-poor countries, disease presents as large-scale waterborne epidemics, and few epidemics have spread through person-to-person contact; however, endemic diseases within these countries can potentially spread through person-to-person contact or fecally contaminated water and foods. Vertical transmission of HEV from infected mother to fetus causes high fetal and perinatal mortality. Other means of transmission, such as zoonotic transmission, can fluctuate depending upon the region and strain of the virus. For instance, zoonotic transmission can sometimes play an insignificant role in human infections, such as in India, where human and pig HEV infections are unrelated. However, recently China and Southeast Asia have experienced a zoonotic spread of HEV-4 from pigs to humans and this has become the dominant mode of transmission of hepatitis E in eastern China. Zoonotic HEV infections in humans occur by eating undercooked pig flesh, raw liver, and sausages; through vocational contact; or via pig slurry, which leads to environmental contamination of agricultural products and seafood. Lastly, blood transfusion-associated HEV infections occur in many countries and screening of donors for HEV RNA is currently under serious consideration. To summarize, HEV genotypes 1 and 2 cause epidemic and endemic diseases in resource poor countries, primarily spreading through contaminated drinking water. HEV genotypes 3 and 4 on the other hand, cause autochthonous infections in developed, and many developing countries, by means of a unique zoonotic food-borne transmission.

Incidence and seroprevalence of hepatitis E virus infection in pregnant women infected with hepatitis B virus and antibody placental transfer in infants

BACKGROUND

Hepatitis E has poor outcomes in pregnant women. Superinfection of hepatitis E virus (HEV) in patients infected with hepatitis B virus (HBV) may worsen liver disease.

OBJECTIVES

To estimate the incidence and seroprevalence of HEV infection among HBV-infected pregnant women, to investigate the transplacental transfer of maternal anti-HEV IgG, and to compare the maternal and neonatal outcomes in anti-HEV positive and negative pregnant women.

STUDY DESIGN

Totally 391 HBV-infected pregnant women were recruited from April 2012 to October 2014. Paired mothers and infants were followed up at an average 9.8 months postpartum. Anti-HEV IgG and IgM were tested by ELISA.

RESULTS

Of the pregnant women, none was anti-HEV IgM positive and 42 (10.7%) were IgG positive. At the follow-up, 3 seronegative women converted to anti-HEV IgG positive, with an estimated incidence of 17 per 1000 person-years. No significant differences of gestational age, preterm birth rate, Apgar score and birthweight were observed between newborns of anti-HEV IgG positive and negative mothers. Of the 42 neonates born to anti-HEV IgG positive mothers, 38 (90.5%) had anti-HEV IgG in their cord blood. The neonatal and maternal anti-HEV IgG levels were positively correlated (r=0.827, p<0.05). All infants were negative for both anti-HEV IgM and IgG at the follow-up.

CONCLUSIONS

HBV-infected pregnant women rarely have novel HEV infection during late pregnancy in Jiangsu, China. Maternal anti-HEV IgG efficiently transfers into the fetuses, and disappears in infants before 10 months old.

Epidemiology of hepatitis E virus in Iran

Iran is known as an endemic country for hepatitis E virus (HEV) infection, while there are variations in the epidemiology of HEV infection throughout the country. The available epidemiological studies in different regions of Iran show HEV seroprevalence of 1.1%-14.2% among general population, 4.5% -14.3% among blood donors, 6.1%-22.8% among injecting drug users, 6.3%-28.3% among hemodialysis patients, 1.6%-11.3% among patients infected with other hepatitis viruses, 27.5% among patients with chronic liver disease, 30.8% among kidney transplant recipient patients, and 10%-16.4% among human immunodeficiency virus-infected patients. These variations reflect differences in the status of public health and hygiene, risk factors, and routes of transmission in different regions and groups. Therefore, it is necessary to review the epidemiology of HEV infection to determine the most prevalent risk factors and routes of transmission, and to evaluate the effectiveness of preventive strategies employed in the public health services of the country. Moreover, the other epidemiological aspects of HEV, including the genotypic pattern, extra hepatic manifestations, and incidence of chronic infection need to be investigated among Iranian population to expand the current knowledge on the epidemiology of HEV and to clarify the real burden of HEV infection. Therefore, this review was performed to provide a general overview regarding the epidemiology of HEV in Iran.

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.

Declining prevalence of hepatitis E antibodies among Danish blood donors

BACKGROUND

The increasing incidence of reported hepatitis E cases in Europe has focused attention on hepatitis E virus (HEV) and the risk of transfusion-transmitted hepatitis E. The aim of this study was to investigate the prevalence of antibodies to HEV (anti-HEV) among Danish blood donors in 2013 and to compare it to previous studies in Denmark. In addition we wanted to compare the relative reactivity of two different assays.

STUDY DESIGN AND METHODS

Samples from 504 blood donors were collected and analyzed for anti-HEV with an in-house assay developed at the National Institutes of Health (NIH). In addition the samples were analyzed with the Wantai anti-HEV assay. Demographic information and possible HEV exposure was collected by self-administered questionnaire.

RESULTS

Using the NIH assay the prevalence of anti-HEV among Danish blood donors was 10.7% and with the Wantai assay the prevalence of anti-HEV was 19.8% (p < 0.001). In both cases the presence of anti-HEV was significantly correlated with increasing age. In addition, anti-HEV as measured by the Wantai test was significantly associated with contact with children (p = 0.01), but in multivariate analysis only age was associated with anti-HEV in both assays. By the NIH assay, the prevalence had declined from 20.6% in 2003 to 10.7% in 2013.

CONCLUSIONS

Anti-HEV prevalence had decreased by half among Danish blood donors over 10 years, but was still highly prevalent. The difference in reactivity of the two assays demonstrates the importance of using the same assay when comparing the anti-HEV prevalence in populations over time.

Hepatitis E virus among persons who inject drugs, San Diego, California, USA, 2009-2010

Data about prevalence of hepatitis E virus infection in persons who inject drugs are limited. Among 18–40-year-old persons who inject drugs in California, USA, prevalence of antibodies against hepatitis E virus was 2.7%. This prevalence was associated with age but not with homelessness, incarceration, or high-risk sexual behavior.

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.

Epidemiological and clinical features of HEV infection: a survey in the district of Foggia (Apulia, Southern Italy)

In this study we assessed the seroprevalence of hepatitis E virus (HEV) infection in both the Italian population and immigrants from developing countries in Foggia (Apulia, Southern Italy). The seroprevalence of HEV was determined in 1217 subjects [412 (34%) immigrants and 805 Italian subjects (blood donors, general population, HIV-positive, haemodialysis patients)]. Serum samples were tested for anti-HEV and confirmed by Western blot assay; in positive patients HEV RNA and genotype were also determined. There were 8·8% of patients that were positive to anti-HEV, confirmed by Western blot. The prevalence in immigrants was 19·7%, and in Italians 3·9% (blood donors 1·3%, general population 2·7%, HIV-positive patients 2·0%, haemodialysis patients 9·6%). Anti-HEV IgM was found in 38/107 (35·5%) of the anti-HEV-positive serum samples (34 immigrants, four Italians). This study indicates a higher circulation of HEV in immigrants and Italian haemodialysis patients, whereas a low prevalence of HEV antibodies was seen in the remaining Italian population.

Hepatitis E virus infection in patients infected with the human immunodeficiency virus

Hepatitis E virus (HEV) is a newly-identified causative agent of acute and chronic hepatitis in severely immunocompromized patients. The present study sought to assess the prevalences of past, recent, on-going, and chronic HEV infections in patients infected with human immunodeficiency virus (HIV) in Marseille, South-eastern France, and to determine if they were correlated with the patients' immunological status or with cirrhosis. Anti-HEV IgG and IgM and HEV RNA testing were concurrently performed on the plasma from 184 patients infected with HIV, including 81 with a CD4+ T-lymphocyte count (CD4 count) <50 cells/mm(3) and 32 with a cirrhosis. Prevalence of anti-HEV IgG and IgM was 4.4% (8/184) and 1.6% (3/184), respectively. Past, recent, and on-going infections were observed in 3.3% (6/184), 1.6% (3/184), and 0.5% (1/184) of the patients, respectively. Anti-HEV antibodies prevalence did not differ significantly according to CD4 count, cirrhosis, sex, age, mode of HIV transmission, and infection with hepatitis B or C virus. Anti-HEV IgG seroreversion was observed in two patients. The patient whose plasma tested positive for HEV RNA had a CD4 count <50 cells/mm(3) ; HEV genotype was 3f. In this patient, longitudinal testing showed HEV RNA positivity during a 10-month period, indicating chronic HEV infection; in contrast, anti-HEV IgG never tested positive. Further studies are needed to evaluate the performance of commercial HEV serological assays in patients infected with HIV and to assess the actual incidence, prevalence, and outcome of HEV infection in this special group of patients. HEV RNA testing is necessary for such purposes.

Hepatitis E virus infection in sheltered homeless persons, France

To determine the prevalence of hepatitis E virus (HEV) infection among sheltered homeless persons in Marseille, France, we retrospectively tested 490 such persons. A total of 11.6% had immunoglobulin (Ig) G and 2.5% had IgM against HEV; 1 person had HEV genotype 3f. Injection drug use was associated with IgG against HEV.

Hepatitis E virus infection as a cause of graft hepatitis in liver transplant recipients

Hepatitis E virus (HEV) infection induces self-limiting liver disease in immunocompetent individuals. Cases of chronic hepatitis E have recently been identified in organ transplant recipients. We questioned if chronic hepatitis E plays a role in graft hepatitis after liver transplantation in a low endemic area. Two hundred twenty-six liver transplant recipients, 129 nontransplanted patients with chronic liver disease, and 108 healthy controls were tested for HEV antibodies. HEV RNA was investigated in all sera from transplanted patients. HEV antibodies were detected in 1 healthy control (1%), 4 patients with chronic liver disease (3%), and 10 liver transplant recipients (4%). Three liver transplant patients also tested positive for HEV RNA. Two of them developed persistent viremia with HEV genotype 3. The patients were anti-HEV immunoglobulin G-negative and HEV RNA-negative before transplantation and had an episode of acute hepatitis 5 or 7 months after transplantation, which led to advanced liver fibrosis after 22 months in 1 patient. Seroconversion to anti-HEV occurred not before 4 months after the first detection of HEV RNA. The possibility of reverse zoonotic transmission was experimentally confirmed by the infection of 5 pigs with a patient's serum. The pigs showed histological inflammation in the liver, and HEV RNA was detectable in different organs, including muscle. In conclusion, the prevalence of HEV infection in Central European liver transplant recipients is low; however, chronic hepatitis E may occur and needs to be considered in the differential diagnosis of graft hepatitis. The diagnosis of HEV infection should be based on HEV RNA determination in immunosuppressed patients. We suggest that immunocompromised individuals should avoid eating uncooked meat and contact with possibly HEV-infected animals.

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.

[Sexually transmissible hepatitis viruses]

The transmission of hepatitis viruses as a result of sexual activity is a common problem in medical practice. A system of stages is proposed to diagnose viral hepatitis. Testing for anti-HBc, HBsAg, anti-HAV and anti-HCV is sufficient for initial screening. Depending on the circumstances, this may be followed by further tests for HBV, HCV and HAV. If initial screening provides no evidence, further tests for HEV, Epstein-Barr virus, cytomegalovirus or other agents are conducted.

Hepatitis E: a complex and global disease

Thirty years after its discovery, the hepatitis E virus (HEV) continues to represent a major public health problem in developing countries. In developed countries, it has emerged as a significant cause of non-travel-associated acute hepatitis. HEV infects a wide range of mammalian species and a key reservoir worldwide appears to be swine. Genomic sequence similarity between some human HEV genotypes and swine HEV strains has been identified and we know that humans can acquire HEV infection from animals. Although for the most part the clinical course of HEV infection is asymptomatic or mild, significant risk of serious disease exists in pregnant women and those with chronic liver disease. In addition, there are data on the threat of chronic infections in immunocompromised patients. Beyond management of exposure by public health measures, recent data support that active immunisation can prevent hepatitis E, highlighting the need for vaccination programmes. Here we review the current knowledge on HEV, its epidemiology, and the management and prevention of human disease.

Time trend of the prevalence of hepatitis E antibodies among farmers and blood donors: a potential zoonosis in Denmark

BACKGROUND

Antibody to hepatitis E virus (anti-HEV) is prevalent in Western countries, where clinical hepatitis E is rarely reported. The aim of this study was to determine the prevalence of anti-HEV among Danish blood donors and Danish farmers. In addition, we compared the prevalence among 2 sets of serum samples obtained from blood donors 20 years apart.

METHODS

Samples from 291 Danish farmers and 169 blood donors that were collected in 1983 and samples from 461 blood donors that were collected in 2003 were tested for anti-HEV. Relevant information on HEV exposure was collected by self-administered questionnaire.

RESULTS

Anti-HEV testing was performed on samples after 20 years of storage at -20 degrees C. The prevalence of anti-HEV was 50.4% among farmers and 32.9% among donors in 1983 and 20.6% among donors in 2003 (P < .05). Presence of anti-HEV was significantly correlated with increasing age in all 3 groups (P < .05). Among donors who had serum samples obtained in 2003, age, contact with horses, and the presence of antibody to hepatitis A virus were associated with the presence of anti-HEV in multivariate analysis. Among farmers, only age was independently associated with the presence of anti-HEV.

CONCLUSION

Anti-HEV was highly prevalent among Danes but has decreased in prevalence over the past 50 years. Our study supports the hypothesis that HEV infection in Denmark may be an asymptomatic zoonotic infection.

Characterization of hepatitis E-specific cell-mediated immune response using IFN-gamma ELISPOT assay

In developing countries, hepatitis E (HEV) and hepatitis A (HAV) are the major causes of acute viral hepatitis with similar feco-oral modes of transmission. In contrast to the high seroprevalence of hepatitis A infection, a low seroprevalence of HEV among children in endemic areas has been reported. These data suggest the possibility that silent HEV infection is undiagnosed by the current available methods. Many of the serological tests used for HEV diagnosis have poor specificity and are unable to differentiate among different genotypes of HEV. Moreover, the RT-PCR used for HEV isolation is only valid for a brief period during the acute stage of infection. Cell-mediated immune (CMI) responses are highly sensitive, and long lasting after sub-clinical infections as shown in HCV and HIV. Our objective was to develop a quantitative assay for cell-mediated immune (CMI) responses in HEV infection as a surrogate marker for HEV exposure in silent infection. Quantitative assessment of the CMI responses in HEV will also help us to evaluate the role of CMI in HEV morbidity. In this study, an HEV-specific interferon-gamma (IFN-gamma) ELISPOT assay was optimized to analyze HEV-specific CMI responses. We used peripheral blood mononuclear cells (PBMC) and sera from experimentally infected chimpanzees and from seroconverted and control human subjects to validate the assay. The HEV-specific IFN-gamma ELISPOT responses correlated strongly and significantly with anti-HEV ELISA positive/negative results (rho=0.73, p=0.02). Moreover, fine specificities of HEV-specific T cell responses could be identified using overlapping HEV ORF2 peptides.

Human herpesvirus 8 and human herpesvirus 2 infections in prison population

Incarcerated persons have high rates of infectious diseases. Few data on the prevalence of sexually transmitted diseases in prisoners are available. This multi-center cross-sectional study enrolled 973 inmates from eight Italian prisons. Demographic and behavioral data were collected using an anonymous standardized questionnaire and antibodies to HIV, HCV, HBV, HSV-2, and HHV-8 were detected in a blood sample obtained from each person at the time of the enrollment in the study. Two hundred and two out of the 973 subjects (20.7%) had antibodies against HHV-8. HHV-8-seropositive subjects were more likely to be older than 30 years with a higher educational level. HHV-8 infection was associated significantly with HBV (P < 0.001) and HSV-2 (P = 0.004) seropositivity and with previous imprisonments. Multivariate analysis showed that HHV-8 infection in Italian inmates was associated with HBV (P < 0.001) and HSV-2 (P = 0.002) seropositivity otherwise among foreigners inmates HHV-8 was significantly associated with HBV infection (P = 0.05). One hundred and eighty-six (21.2%) prisoners had anti-HSV-2 antibodies. At multivariate analysis HSV-2-positivity was significantly associated with HIV (P < 0.001) and HHV-8 infections (P = 0.003), whereas it was inversely associated with HCV infection (0.004). A relatively high seroprevalence of HHV-8 and HSV-2 among Italian prison inmates was found. The association of HHV-8 and HSV-2 infections suggest sexual transmission of these viruses among Italian prison inmates.

[Acute hepatitis E in Madrid: description of 18 cases]

INTRODUCTION

Hepatitis E virus (HEV) is the main cause of non-A non-B enterically transmitted hepatitis in underdeveloped countries but is rare in industrialized areas. However, in the last few years, several sporadic autochthonous hepatitis E cases have been reported in Europe and no risk factors, such as visiting to endemic areas, could be found in these patients.

OBJECTIVE AND PATIENTS

Twelve patients with sporadic autochthonous hepatitis E (no risk factors such as traveling to endemic areas) and six imported cases (travel to Nepal, Santo Domingo, China, Brazil and Ecuador) were studied between June 1999 and December 2005.

RESULTS

HEV infection was diagnosed in patients with symptoms of acute hepatitis and the presence of IgG and IgM antibodies in serum with no other markers of hepatitis. HEV infection is probably overlooked in industrialized countries.

CONCLUSIONS

This diagnosis should be suspected in patients with acute hepatitis and anti-HEV antibodies in serum without known risk factors such as traveling to endemic areas.

Evaluation of diagnostic assays for hepatitis E virus in outbreak settings

Hepatitis E virus (HEV) is a major cause of hepatitis. We evaluated five HEV antibody diagnostic assays by using outbreak specimens. The Abbott immunoglobulin G (IgG), Genelabs IgG, and Walter Reed Army Institute of Research (WRAIR) IgM assays were about 90% sensitive; the Abbott IgG and WRAIR total Ig and IgM assays were more than 90% specific.

Hepatitis E indigenous to economically developed countries: to what extent a zoonosis?

PURPOSE OF REVIEW

Hepatitis E, a disease transmitted by hepatitis E virus, is increasingly recognized as being indigenous to affluent, temperate-zone countries. Issues pertaining to disease acquisition and hepatitis E virus infection, particularly in Western countries, are reviewed and highlighted.

RECENT FINDINGS

Clinical hepatitis E in the West, as in Japan, manifests more commonly in older people (>60 years) and in men, but fulminant hepatitis appears less frequent than in Japan. There, specific gastronomic and culinary risk factors associated with disease are being identified, but in the West, data implicating hepatitis E as being foodborne have yet to emerge. While hepatitis E virus subgenomic sequences in Western case patients are found to be closely related to swine hepatitis E virus, a porcine linkage to their infection remains to be established. Weak associations between occupational contact with pigs and risk of infection have been noted. Findings from earlier studies implicating animals that cohabitate with humans as reservoirs, and sewage as vehicles of infection await confirmation.

SUMMARY

Hepatitis E indigenous to developed countries is a distinct clinico-epidemiological entity. Humans, animals, food and the environment contribute and interact to cause human disease, and to sustain hepatitis E virus endemicity and enzooticity.

Hepatitis E antibody seroconversion without disease in highly endemic rural Egyptian communities

Hepatitis E virus (HEV) is enterically transmitted and causes self-limiting acute viral hepatitis (AVH) primarily in less developed countries. A prospective cohort study to assess incidence of, and risk factors for, seroconversion to HEV (anti-HEV) was conducted in two Egyptian villages with a 67.7% anti-HEV prevalence. Nine hundred and nineteen villagers who were initially anti-HEV-negative were followed for 10.7 months. Thirty-four (3.7%) had strong anti-HEV serologic responses at follow-up giving an estimated anti-HEV incidence of 41.6/1,000 person-years. No significant associations were found between anti-HEV seroincidence and demographic and socioeconomic factors, source of water, household plumbing or sanitation, hand and vegetable washing, ownership of animals, jaundice and many other variables. None of the seroconverting subjects gave a history compatible with AVH during the interval. We hypothesize that both zoonotic and anthroponotic transmission of avirulent (possibly genotype-3) HEV is occurring extensively in these rural villages. An alternative explanation for the lack of morbidity among anti-HEV incident cases could be initial asymptomatic infections occur during early childhood with subsequent antibody titer boosting without illness upon re-exposure to the virus.

Hepatitis E in the south west of France in individuals who have never visited an endemic area

A total of 431 consecutive patients from the Midi Pyrenees area with acute hepatitis with unknown etiology in 2001-2002 were tested for the presence of immunoglobulin G-class (IgG) anti-hepatitis E virus (HEV) antibodies. Forty-six (10.7%) had anti-HEV IgG, and the results were questionable for a further 17 (3.9%). Real time PCR based on TaqMan detection was used to identify HEV genome fragments in the serum of patients with positive or questionable anti-HEV serology. HEV RNA was found in 25.4% of cases. All amplification products were sequenced and analyzed. Phylogenetic analysis revealed that all the strains were genotype 3. In conclusion, virological and epidemiological data indicate that genotype 3 viruses are circulating in the south west part of France (Midi-Pyrenees) in patients with acute hepatitis and who have not visited recently areas in which HEV is endemic.

Routes of transmission of swine hepatitis E virus in pigs

Hepatitis E virus (HEV) is believed to be transmitted by the fecal-oral route in pigs. To date, in experiments, HEV has been transmitted successfully only by the intravenous or intrahepatic route. To assess the route of HEV transmission, 27 pigs were separated into nine groups of three pigs. Positive-control pigs were inoculated intravenously with swine HEV and served as the source of HEV for the other groups. Uninoculated contact pigs were placed in the positive-control group. On three consecutive days, naive pigs were inoculated using samples collected from the positive-control pigs at 9, 10, and 11 days postinoculation. The tonsils and nasal mucosa of each positive-control pig were swabbed and that swab was used to rub the tonsils and nasal and ocular mucosa of naive pigs. The positive-control pigs were also injected with bacterin, and the same needle was used to immediately inject naive pigs. Feces were collected from positive controls and fed by oral gavage to naive pigs. Weekly fecal and serum samples from each pig were tested for anti-HEV antibodies and HEV RNA. All positive-control pigs shed the virus in feces; two pigs were viremic and seroconverted to anti-HEV. All contact control pigs shed the virus in feces; two seroconverted and one became viremic. One of three pigs in the fecal-oral exposure group shed the virus in feces and seroconverted. Pigs exposed to the contaminated needles or the tonsil and nasal secretion swabs remained negative. This is the first report of experimental fecal-oral transmission of HEV in swine.

Immunologically silent autochthonous acute hepatitis E virus infection in France

Hepatitis E is an acute and self-limiting hepatitis, and the causative agent, hepatitis E virus, is excreted in feces and orally transmitted. The disease is common in Asia and Africa, causing outbreaks or sporadic cases. In Europe, the infection is generally observed after a history of travel in an area of endemicity. We report on an autochthonous case in southwestern France in which the diagnosis was based on molecular tools rather than serological testing.

Evidence for the presence of hepatitis E virus in pigs in the United Kingdom

Samples of serum, tissue and faeces from two pig herds in England were examined for hepatitis E virus by reverse-transcriptase PCR (RT-PCR), and a virus strain from each herd was partially sequenced. Eleven of 42 faecal samples and 16 of 21 tissue samples from two pigs were positive for the virus by RT-PCR. Analysis of two unique but closely related nucleotide sequences obtained from the two herds showed that the viruses clustered in genotype III (6) with a human strain of the virus from an autochthonously acquired case of acute hepatitis in the UK. An ELISA based on recombinant open reading frame 2 (ORF-2) was used to detect antibodies to hepatitis E virus in 256 pig sera from the UK; 85.5 per cent of the samples were positive, compared with 58 per cent of similar samples from Swedish pigs and 23.5 per cent of samples from Dutch pigs.

GB virus C epidemiology in Denmark: different routes of transmission in children and low- and high-risk adults

With the demonstration of an effect of GBV-C infection on the outcome of HIV infection, it has become important to understand the epidemiology of GBV-C. The purpose of this study was to determine the prevalence in high- and low-risk populations. The following populations were tested: school children, 9 and 15 years of age (n = 901), blood donors (n = 5,203), hospital employees (n = 1,432), and prisoners and injecting drug users (n = 447). In-house RT-PCR for GBV-CRNA was used together with a commercial ELISA for anti-E2 (Boehringer, Germany). In addition, questionnaires for risk factors for transmission and serological tests for HIV and hepatitis were applied. The overall prevalence of GBV-CRNA was 1.4% among children, 2.2% among blood donors, 2.2% among hospital employees, 12.5% among non-injecting prisoners, and 34.9% among drug injectors. Correspondingly anti-E2 was found in 0.3%, 12.3%, 25.0%, and 42.7%. Among hospital employees, independent risk factors for GBV-C were professions with blood exposure and sexual risk partners. Among prisoners and drug users, injecting and a sexual risk index were associated independently with GBV-C. Based on these results, the following hypothesis is suggested: GBV-C is transmitted frequently at birth or early childhood and this leads to chronic infection in most cases. Sexual transmission is the most important route of transmission in the adult population but this infection is usually transient. Blood borne transmission plays a role among health care workers and injecting drug users and GBV-C should be further evaluated as a surrogate marker for professional blood exposure.