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.

Prevalence of Hepatitis E Virus Infection Among Blood Donors in the Eastern Province of Saudi Arabia

PURPOSE

Hepatitis E virus (HEV) causes acute hepatitis in humans and constitutes a major problem for immunocompromised patients, patients with hematological diseases, and pregnant women. It is transmitted mainly through fecal oral route; however, transmission through blood and blood products is reported globally and becoming a health concern. We sought to determine the prevalence of HEV among blood donors in the Eastern Province of Saudi Arabia using molecular as well as serological assays to assess the safety of blood transfusion and the need for HEV screening among blood donors.

PATIENTS AND METHODS

A total of 806 whole blood samples were collected from blood donors between May and November 2020 and tested for anti-HEV IgG and IgM antibodies by ELISA and for HEV RNA by RT-PCR.

RESULTS

The overall seroprevalence of HEV IgG antibodies was 3.2% with no statistically significant difference between the non-Saudis (3.28%) and Saudis (3.17%) (p value 0.929) or between males (3.14%) and females (4.88%) (p value 0.527). None of the IgG positive individuals had IgM antibodies. HEV RNA was not detected in any of the blood donors.

CONCLUSION

HEV seroprevalence is low among blood donors in the Eastern Province of Saudi Arabia and may constitute minimal risk for transfusion associated infections.

The seropervelance of infectious hepatitis viruses (HBV, HCV and HEV) among blood donors and their correlation to risk factors in Qena governorate, Upper Egypt

This study was performed to determine the prevalence of HBV and HCV infection among blood donors and the occurrence of HEV in hepatitis viruses seropositive blood donors. Also, to investigate the correlation between the occurrence of hepatitis viruses and other risk factors (gender, age, occupation, educational level, residency and donors' types). A total of 11,604 blood samples from apparently healthy blood donors of age range 18-60 years old were collected. The blood donors were categorized as voluntary and replacement donors. Blood samples from donors were tested for the presence of HBsAg, HCV and HEV antibodies by using Enzyme-linked immunosorbent assay. The overall results indicated that 671 out of 11,604 blood donors; 370 persons (3.188%) HCV, 295 persons (2.542%) HBV and 6 persons (0.052%) HCV and HBV; were hepatitis viruses seropositive donors. The prevalence of HEV were 193 (28.76%) among these seropositive blood donors. There is a highly significant correlation among HCV, HBV and other risk factors. Also, the HEV showed high significant with age and educational level and significant with donor types and locations. All investigated virus combinations (HEV/HCV, HEV/HBV and HEV/HCV/HBV) were highly significant with the risk factors except for occupation. In conclusion, the HEV is significantly correlated to HCV and HBV seropositive donors and should be screened among blood donors.

Prevalence of hepatitis E viraemia among blood donors: a systematic review

BACKGROUND

Hepatitis E virus (HEV) is usually transmitted by faecal-oral route. Recent reports have documented HEV viraemia in donated blood units and HEV transmission through blood transfusion. This systematic review summarizes the available data on prevalence of HEV viraemia in blood donors.

METHODS

Electronic databases were searched on 17 December 2018 to identify full-text English papers reporting original data on prevalence of HEV RNA in donated blood units. Two authors independently extracted the relevant data, which were pooled using simple aggregation as well as a random-effects meta-analysis; heterogeneity was assessed using the I2 method.

RESULTS

In all, 59 data sets from 28 countries were identified. The available data showed marked heterogeneity. Of a total of 2 127 832 units studied, 561 (263·6 [95% confidence intervals = 242·7-286·4] per million units) tested positive for HEV RNA. On random-effects meta-analysis, the pooled prevalence was 60·9 [6·7-155·4] per million units. In the viraemic units, HEV RNA titre varied by nearly one million-fold, and most had genotype 3 HEV. The prevalence was higher in blood units with anti-HEV antibodies or elevated alanine aminotransferase. Only nearly one-fourth of viraemic units had anti-HEV antibodies.

CONCLUSIONS

The prevalence of HEV viraemia among healthy blood donors is low, though the available data had limited geographical representation and marked heterogeneity. There is a need for further data on HEV viraemia in blood donors from areas with non-3 HEV genotype preponderance.

Noninvasive models for predicting poor prognosis of chronic HBV infection patients precipitating acute HEV infection

Hepatitis E virus (HEV) infection contributes to a considerable proportion of acute-on-chronic liver failure (ACLF) in patients with chronic hepatitis B virus (HBV) infection. This study aimed to predict the prognosis of chronic HBV infection patients precipitating acute HEV infection. A total of 193 patients were enrolled in this study. The performances of three chronic liver disease prognostic models (CTP score, MELD score, and CLIF-C ADs) were analyzed for predicting the development of ACLF following HEV superimposing chronic HBV infection. Subsequently, the performances of five ACLF prognostic assessment models (CTP score, MELD score, CLIF-C ACLFs, CLIF-C OFs, and COSSH-ACLFs) were analyzed for predicting the outcome of those ACLF patients. Of 193 chronic HBV infection patients precipitating acute HEV infection, 13 patients were diagnosed ACLF on admission, 54 patients developed to ACLF after admission, and 126 patients had non-ACLF during the stay in hospital. For predicting the development of ACLF, CTP score yielded a significantly higher AUROC compared with MELD score and CLIF-C ADs (0.92, 0.88, and 0.86, respectively; all p < 0.05). For predicting the poor prognosis of ACLF patients, the COSSH-ACLFs yielded a significantly higher AUROC compared with CLIF-C ACLFs, CLIF-C OFs, MELD score, and CTP score (0.89, 0.83, 0.81, 0.67, and 0.58, respectively; all p < 0.05). In conclusion, the stepwise application of CTP score and COSSH-ACLFs can predict the prognosis of chronic HBV infection patients precipitating acute HEV infection.

Thrombotic thrombocytopenic purpura relapse induced by acute hepatitis E transmitted by cryosupernatant plasma and successfully controlled with ribavirin

BACKGROUND

Hepatitis E virus (HEV) can be transmitted by transfusion of any type of blood component, but there are few data on the potential risk of transmitting this virus and the associated complications. We provide evidence that HEV can be transmitted by cryosupernatant plasma, and that HEV infection can act as a trigger for thrombotic thrombocytopenic purpura (TTP).

STUDY DESIGN AND METHODS

A patient with a history of TTP treated with plasmapheresis 2 months previously developed jaundice and a TTP exacerbation with purpura, thrombocytopenia, schistocytes, and undetectable ADAMTS-13 activity. He was diagnosed with acute hepatitis E and treated with ribavirin. TTP remitted with remission of HEV infection.

RESULTS

Traceback to determine the source of the infection showed that 1 cryosupernatant plasma among the 99 different blood components used for the patient's last plasmapheresis was positive for HEV RNA, with an estimated viral load of 5000 to 10,000 IU/mL. Phylogenetic analysis proved the transfusion-transmitted route of acute hepatitis E.

CONCLUSION

In a patient with TTP, acute HEV infection transmitted by cryosupernatant plasma may trigger exacerbation of TTP, which can be controlled on remission of HEV infection with ribavirin.

Prevalence of hepatitis E virus infection among blood donors in mainland China: a meta-analysis

BACKGROUND

The risk of hepatitis E virus (HEV) infection from blood transfusion has raised increasing concern in many countries. Several transfusion-transmitted cases have been described in the United Kingdom and Japan. The objective was to investigate the prevalence of HEV infection among Chinese blood donors and analyze the potential risk of HEV infection through blood transfusion in China.

STUDY DESIGN AND METHODS

Major English and Chinese research databases were used as background research for the study of locations, years, and the number of HEV infections among blood donors in China. The pooled, estimated rate of HEV infection was calculated. Subgroup analyses, for age, sex, and alanine aminotransferase (ALT) levels were performed using software for comprehensive meta-analysis.

RESULTS

The pooled rates of anti-HEV IgM- and anti-HEV IgG-positive donations were 1.09% (95% confidence interval [CI], 0.95%-1.26%) and 30% (95% CI, 25%-34%), respectively. The prevalence of anti-HEV IgM was significantly higher in donors with elevated ALT (4.34%) compared with the rate in donors with normal ALT (1.35%; χ²  = 39.66, p < 0.01). The anti-HEV IgM and IgG rates were higher in the Southwest region (1.58 and 41%, respectively) compared to the rates in other regions of China (chi-square test, p < 0.05). The anti-HEV IgG rate was also significantly higher in donors 30 years and older compared with donors between 18 and 29 years of age (39% vs. 22%, respectively; χ²  = 1457.10, p < 0.01). Genetic analysis of HEV from RNA-positive donors indicated that the majority of HEV infections were Genotype 1 (19/33 = 58%), while the remaining 14 isolates were Genotype 4 (14/33 = 42%; χ²  = 0.758, p > 0.05).

CONCLUSION

Qualified donations after routine blood donor screening still carry a potential risk for transmitting HEV. The major genotypes in Chinese donors in this study were Genotypes 1 and 4.

Hepatitis E virus seroepidemiology: a post-earthquake study among blood donors in Nepal

Background

As one of the causative agents of viral hepatitis, hepatitis E virus (HEV) has gained public health attention globally. HEV epidemics occur in developing countries, associated with faecal contamination of water and poor sanitation. In industrialised nations, HEV infections are associated with travel to countries endemic for HEV, however, autochthonous infections, mainly through zoonotic transmission, are increasingly being reported. HEV can also be transmitted by blood transfusion. Nepal has experienced a number of HEV outbreaks, and recent earthquakes resulted in predictions raising the risk of an HEV outbreak to very high. This study aimed to measure HEV exposure in Nepalese blood donors after large earthquakes.

Methods

Samples (n = 1,845) were collected from blood donors from Kathmandu, Chitwan, Bhaktapur and Kavre. Demographic details, including age and sex along with possible risk factors associated with HEV exposure were collected via a study-specific questionnaire. Samples were tested for HEV IgM, IgG and antigen. The proportion of donors positive for HEV IgM or IgG was calculated overall, and for each of the variables studied. Chi square and regression analyses were performed to identify factors associated with HEV exposure.

Results

Of the donors residing in earthquake affected regions (Kathmandu, Bhaktapur and Kavre), 3.2% (54/1,686; 95% CI 2.7–4.0%) were HEV IgM positive and two donors were positive for HEV antigen. Overall, 41.9% (773/1,845; 95% CI 39.7–44.2%) of donors were HEV IgG positive, with regional variation observed. Higher HEV IgG and IgM prevalence was observed in donors who reported eating pork, likely an indicator of zoonotic transmission. Previous exposure to HEV in Nepalese blood donors is relatively high.

Conclusion

Detection of recent markers of HEV infection in healthy donors suggests recent asymptomatic HEV infection and therefore transfusion-transmission in vulnerable patients is a risk in Nepal. Surprisingly, this study did not provide evidence of a large HEV outbreak following the devastating earthquakes in 2015.

Sero-Epidemiological Study of Hepatitis E Virus among Thalassemia as High Risk Patients: A Cross-Sectional Survey in Jahrom, Southern, Iran

Hepatitis E virus (HEV) could be cause of viral hepatitis in the developing countries and cause severe epidemics. According to other studies, blood transfusion as a probable route of HEV infection has been suggested. An infection with hepatitis agents such as HEV causes active liver failure in multi-transfusion patients in particular thalassemia. The purpose of this study determines the seropositivity of anti-HEV antibodies in thalassemia individuals in Jahrom. In a cross-sectional study, sera from 110 thalassemia were collected between 2013 and 2014. Enzyme-linked immunosorbent assay (ELISA) method was performed to detection of anti-HEV antibodies. Individuals’ data were collected such as, demographic and clinical, for statistical analysis. Our results show that 10% and 1.8% of the enrolled patients were HEV Ig-G and Ig-M positive antibodies respectively. In addition, there was statiscally significant difference in age groups for prevalence of anti-HEV Ig-G (P = 0.01). Also the serum levels of liver enzymes such as ALT and AST in the HEV Ig-G and Ig-M positive samples were significantly higher than anti-HEV negative samples. But there were no significant difference between sex and splenectomy with anti-HEV positive samples. The results indicate more study are needed to assess HEV screening of blood products to these patients that those have a probably risk of exposure to HEV especially in higher years old.