Fulminant Transfusion-Associated Hepatitis E Virus Infection Despite Screening, England, 2016-2020

HEV in Blood Donors in Switzerland: The Route to Safe Blood Products

The hepatitis E virus (HEV) is an emerging infectious disease with zoonotic potential, causing acute hepatitis in humans. Infections in healthy individuals are often acute, self-limiting and asymptomatic, thus leading to the underdiagnosis of HEV infections. Asymptomatic HEV infections pose a problem for blood transfusion safety by increasing the risk for transfusion-transmitted HEV infections. Here, we describe the journey from determining the HEV seroprevalence among blood donors to the implementation of routine HEV RNA testing of all blood products in Switzerland in 2018 and summarise the HEV cases detected since. In total, 290 HEV-positive blood donations were detected by mini-pool nucleic acid testing (NAT) in Switzerland in the period of October 2018-December 2023, equal to an incidence of 20.7 per 100,000 donations. Thanks to the implemented scheme, no transfusion-transmitted infections occurred in this period. Furthermore, blood donation monitoring has proven to be an effective means of detecting HEV outbreaks in the general population. HEV cases in Swiss blood donors are caused by two major genotypes, the Swiss-endemic subtypes 3h3 and 3c. Interestingly, 11 HEV cases (5%) were of genotype 3ra, a variant found in wild and farmed rabbits. Our results indicate that mini-pool NAT is an efficient method to reduce the risk of transfusion-transmitted HEV infections.

Assessment of Hepatitis E virus transmission risks: a comprehensive review of cases among blood transfusion recipients and blood donors

Background

Hepatitis E Virus is a major cause of acute and fulminant hepatitis, particularly in developing countries. While the virus is commonly spread through the fecal-oral route, numerous cases of transfusion transmitted Hepatitis E Virus (TT-HEV) have been reported, raising concerns about its transmission via blood transfusions, especially in industrialized countries. The high prevalence of antibodies and viremia among asymptomatic blood donors further heightens the risk of transfusion-related transmission. However, there is still debate about the best strategy to minimize TT-HEV.

Objective

The review was conducted to Summarize the literature on TT-HEV infection cases and the prevalence of HEV among blood donors.

Methods

The databases PubMed, Scopus, Web of Science, Embase, and CINAHL were searched for relevant studies from 2000 to 2022.Serological and molecular screening data of HEV in blood donors were used to gather prevalence and incidence rates.TT-HEV cases were reviewed by examining evidence of HEV infection before and after transfusion.

Results

A total of 121 manuscripts reports the prevalence and incidence of HEV among blood donors and cases of TT-HEV. Twenty-six articles reported confirmed cases of TT-HEV and 101 articles reported on HEV prevalence or incidence among blood donors.

Conclusion

TT-HEV transmission through blood products is a real concern, especially for immunocompromised patients.The risk and severity of infection could vary between immunocompetent and immunosuppressed patients.To increase transfusion safety, the evaluation recommends HEV screening protocols, especially in endemic region.

Hepatitis E Virus in the United States and Canada: Is It Time to Consider Blood Donation Screening?

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis in the world and can lead to severe complications in immunocompromised individuals. HEV is primarily transmitted through eating pork, which has led to an increased in anti-HEV IgG seropositivity in the general population of Europe in particular. However, it can also be transmitted intravenously, such as through transfusions. The growing evidence of HEV contamination of blood products and documented cases of transmission have given rise to practice changes and blood product screening of HEV in many European countries. This review covers the abundant European literature and focuses on the most recent data pertaining to the prevalence of HEV RNA positivity and IgG seropositivity in the North American general population and in blood products from Canada and the United States. Currently, Health Canada and the Food and Drug Administration do not require testing of HEV in blood products. For this reason, awareness among blood product prescribers about the possibility of HEV transmission through blood products is crucial. However, we also demonstrate that the province of Quebec has a prevalence of anti-HEV and HEV RNA positivity similar to some European countries. In light of this, we believe that HEV RNA blood donation screening be reevaluated with the availability of more cost-effective assays.

Prevalence of Acute Hepatitis E Virus Infections in Swiss Blood Donors 2018-2020

INTRODUCTION

Hepatitis E virus (HEV) genotype 3 is the major cause of acute viral hepatitis in several European countries. It is acquired mainly by ingesting contaminated pork, but has also been reported to be transmitted through blood transfusion. Although most HEV infections, including those via blood products, are usually self-limiting, they may become chronic in immunocompromised persons. It is thus essential to identify HEV-infected blood donations to prevent transmission to vulnerable recipients.

AIMS

Prior to the decision whether to introduce HEV RNA screening for all Swiss blood donations, a 2-year nationwide prevalence study was conducted.

METHODS

All blood donations were screened in pools of 12-24 samples at five regional blood donation services, and HEV RNA-positive pools were subsequently resolved to the individual donation index donation (X). The viral load, HEV IgG and IgM serology, and HEV genotype were determined. Follow-up investigations were conducted on future control donations (X + 1) and previous archived donations of the donor (X - 1) where available.

RESULTS

Between October 2018 and September 2020, 541,349 blood donations were screened and 125 confirmed positive donations were identified (prevalence 1:4331 donations). At the time of blood donation, the HEV RNA-positive individuals were symptom-free. The median viral load was 554 IU/mL (range: 2.01-2,500,000 IU/mL). Men (88; 70%) were more frequently infected than women (37; 30%), as compared with the sex distribution in the Swiss donor population (57% male/43% female, p < 0.01). Of the 106 genotyped cases (85%), all belonged to genotype 3. Two HEV sub-genotypes predominated; 3h3 (formerly 3s) and 3c. The remaining sub-genotypes are all known to circulate in Europe. Five 3ra genotypes were identified, this being a variant associated with rabbits. In total, 85 (68%) X donations were negative for HEV IgM and IgG. The remaining 40 (32%) were positive for HEV IgG and/or IgM, and consistent with an active infection. We found no markers of previous HEV in 87 of the 89 available and analyzed archive samples (X - 1). Two donors were HEV IgG-positive in the X - 1 donation suggesting insufficient immunity to prevent HEV reinfection. Time of collection of the 90 (72%) analyzed X + 1 donations varied between 2.9 and 101.9 weeks (median of 35 weeks) after X donation. As expected, none of those tested were positive for HEV RNA. Most donors (89; 99%) were positive for anti-HEV lgG/lgM (i.e., seroconversion). HEV lgM-positivity (23; 26%) indicates an often-long persistence of lgM antibodies post-HEV infection.

CONCLUSION

The data collected during the first year of the study provided the basis for the decision to establish mandatory HEV RNA universal screening of all Swiss blood donations in minipools, a vital step in providing safer blood for all recipients, especially those who are immunosuppressed.

Universal nucleic acid donor screening revealed epidemiological features of hepatitis E and prevented transfusion-transmitted infection in Japan

BACKGROUND

More than 45 cases of transfusion-transmitted hepatitis E virus infection (TT-HEV) have been reported in Japan. Therefore, in 2020, universal individual donation nucleic acid amplification testing (ID-NAT) was implemented for HEV.

STUDY DESIGN AND METHODS

We characterized HEV NAT-positive blood donors. The number of new HEV infections and the asymptomatic infection rate were estimated using the HEV NAT-positive rate. HEV RNA quantitation, phylogenetic analysis, and antibody tests were performed, and the residual risk of TT-HEV was assessed based on the lookback study results.

RESULTS

A total of 5,075,100 blood donations were screened with ID-NAT during the first year of implementation, among which 2804 (0.055%; males: 0.060%, females: 0.043%) were NAT-positive with regional differences. Approximately 270,000 new HEV infection cases were estimated to occur annually in Japan, with an asymptomatic infection rate of 99.9%. The median HEV RNA concentration, excluding cases below the limit of quantification, was 205 IU/mL. Among the 1113 cases where the genotype could be determined, HEV-3 and HEV-4 accounted for 98.8% (1100) and 1.2% (13), respectively. The maximum duration of HEV viremia, including the pre- and post-ID-NAT window periods, was estimated to be 88.2 days. Within the 3 years since ID-NAT implementation, no confirmed cases of breakthrough TT-HEV were observed.

DISCUSSION

Multiple indigenous HEV strains are prevalent in Japan, infecting a significant number of individuals. However, since the implementation of ID-NAT, TT-HEV has been prevented due to the test's high sensitivity.

Clinical performance of a new multiplex assay for the detection of HIV-1, HIV-2, HCV, HBV, and HEV in blood donations in Catalonia (Spain)

BACKGROUND

Commercial multiplex nucleic acid tests (NATs) for HIV-1/HIV-2/HCV/HBV are widely used in developed countries to screen blood donations. HEV NAT screening has been implemented in some blood banks but is tested with a different assay.

STUDY DESIGN AND METHODS

This study describes the clinical sensitivity and specificity of the Procleix® UltrioPlex E (UPxE) assay on the automated Procleix Panther® system for the simultaneous detection of HIV-1/HIV-2/HCV/HBV/HEV. To evaluate routine performance, 10,138 donations were tested in parallel with UPxE (in ID-NAT) and current assays (Procleix Ultrio Elite [UE] assay in ID-NAT and Procleix HEV assay in pool of 16). To assess clinical sensitivity, archived donations positive for HCV, HIV-1, HBV, HEV, or occult HBV infection (OBI) were tested (n = 104-186).

RESULTS

Five donations were initially reactive (IR) with UPxE; none of them were reactive with current assays. Two of the three samples IR for HIV-1/HIV-2/HCV/HBV were confirmed positive for HBV (HBV NAT and/or anti-HBV core positive) and classified as OBI. The two samples IR for HEV were confirmed positive (Procleix HEV assay in ID-NAT and in-house RT-PCR HEV assay). One sample IR for HIV-1/HIV-2/HCV/HBV with UPxE and another with UE were not confirmed. UPxE showed a specificity of 99.99% for HIV-1/HIV-2/HCV/HBV and 100% for HEV. Comparable sensitivities were observed for HIV-1, HCV, HBV, OBI, and HEV samples tested in the UPxE, UE, and Procleix HEV assays.

DISCUSSION

UPxE may provide an efficient solution for the simultaneous detection of HIV-1, HIV-2, HCV, HBV, and HEV in blood donations in a single test.

Longitudinal analysis of annual national hemovigilance data to assess pathogen reduced platelet transfusion trends during conversion to routine universal clinical use and 7-day storage

BACKGROUND

France converted to universal pathogen reduced (PR; amotosalen/UVA) platelets in 2017 and extended platelet component (PC) shelf-life from 5- to 7-days in 2018 and 2019. Annual national hemovigilance (HV) reports characterized longitudinal PC utilization and safety over 11 years, including several years prior to PR adoption as the national standard of care.

METHODS

Data were extracted from published annual HV reports. Apheresis and pooled buffy coat [BC] PC use was compared. Transfusion reactions (TRs) were stratified by type, severity, and causality. Trends were assessed for three periods: Baseline (2010-14; ~7% PR), Period 1 ([P1] 2015-17; 8%-21% PR), and Period 2 ([P2] 2018-20; 100% PR).

RESULTS

PC use increased by 19.1% between 2010 and 2020. Pooled BC PC production increased from 38.8% to 68.2% of total PCs. Annual changes in PCs issued averaged 2.4% per year at baseline, -0.02% (P1) and 2.8% (P2). The increase in P2 coincided with a reduction in the target platelet dose and extension to 7-day storage. Allergic reactions, alloimmunization, febrile non-hemolytic TRs, immunologic incompatibility, and ineffective transfusions accounted for >90% of TRs. Overall, TR incidence per 100,000 PCs issued declined from 527.9 (2010) to 345.7 (2020). Severe TR rates declined 34.8% between P1-P2. Forty-six transfusion-transmitted bacterial infections (TTBI) were associated with conventional PCs during baseline and P1. No TTBI were associated with amotosalen/UVA PCs. Infections with Hepatitis E (HEV) a non-enveloped virus resistant to PR, were reported in all periods.

DISCUSSION

Longitudinal HV analysis demonstrated stable PC utilization trends with reduced patient risk during conversion to universal 7-day amotosalen/UVA PCs.

Prevalence of HEV RNA in Croatian blood donors

OBJECTIVES

HEV infection is asymptomatic for immunocompetent blood donors (BD). Transfused HEV-infected blood products may cause potentially hazardous HEV infection in immunocompromised patients. Evaluation of the need for routine BD HEV RNA screening primarily demands the establishment of HEV infection prevalence in Croatian BD.

MATERIALS AND METHODS

We tested BD samples in ID-NAT with the Procleix UltrioPlex E screening test for simultaneous detection of HBV DNA, HCV RNA, HIV-1,2 RNA, and HEV RNA (Grifols, Spain). HEV infection was confirmed with HEV RNA quantitative test (Altona Diagnostics, Germany) and HEV IgM and HEV IgG antibody test (DIA.PRO Diagnostic Bioprobes, Italy). We analysed the HEV RNA sequence and performed a phylogenetic analysis. We recorded BD's anamnestic data and dietary habits. BDs gave follow-up samples after two months and did not donate blood for six months.

RESULTS

Between December 2021 and March 2022, we tested 8,631 donations and found four HEV RNA-positive donations, which equals to one in 2,158 donations (0.046 %, 95 % confidence interval, 0.018 %-0.119 %). Confirmatory HEV RNA testing gave results from negative to 4.73E + 3 IU/ml HEV RNA. Three donations were in the serological window period. We have genotyped HEV RNA of two infected BD as genotype HEV-3c. Blood donors didn't report any health problems and their diet included pork. Testing on follow-up samples presented seroconversion and no HEV RNA could be detected.

CONCLUSION

The incidence of HEV RNA infection in BD in Croatia corresponds with other European data. The decision on implementation of HEV NAT screening in Croatia needs an expert team evaluation of the possible risk of TT-HEV infection.

Dual Infection of Hepatitis A Virus and Hepatitis E Virus- What Is Known?

Viral hepatitis is an infection of human hepatocytes resulting in liver damage. Dual infection of two hepatotropic viruses affects disease outcomes. The hepatitis A virus (HAV) and hepatitis E virus (HEV) are two enterically transmitted viruses; they are single-stranded RNA viruses and have common modes of transmission. They are transmitted mainly by the fecal-oral route and ingestion of contaminated food, though the HAV has no animal reservoirs. The HAV and HEV cause acute self-limiting disease; however, the HEV, but not HAV, can progress to chronic and extrahepatic infections. The HAV/HEV dual infection was reported among acute hepatitis patients present in developing countries. The impact of the HAV/HEV on the prognosis for acute hepatitis is not completely understood. Studies showed that the HAV/HEV dual infection increased abnormalities in the liver leading to fulminant hepatic failure (FHF) with a higher mortality rate compared to infection with a single virus. On the other hand, other reports showed that the clinical symptoms of the HAV/HEV dual infection were comparable to symptoms associated with the HAV or HEV monoinfection. This review highlights the modes of transmission, the prevalence of the HAV/HEV dual infection in various countries and among several study subjects, the possible outcomes of this dual infection, potential model systems for studying this dual infection, and methods of prevention of this dual infection and its associated complications.

Is Hepatitis E Virus a Neglected or Emerging Pathogen in Egypt?

Though Egypt ranks among the top countries for viral hepatitis and death-related liver disease, Hepatitis E virus (HEV) is a neglected pathogen. Living in villages and rural communities with low sanitation, use of underground well water and contact with animals are the main risk factors for HEV infection. Domestic animals, especially ruminants and their edible products, are one source of infection. Contamination of water by either human or animal stools is the main route of infection. In addition, HEV either alone or in coinfection with other hepatotropic viruses has been recorded in Egyptian blood donors. HEV seropositivity among Egyptian villagers was 60-80%, especially in the first decade of life. Though HEV seropositivity is the highest among Egyptians, HEV infection is not routinely diagnosed in Egyptian hospitals. The initial manifestations of HEV among Egyptians is a subclinical infection, although progression to fulminant hepatic failure has been recorded. With the improvement in serological and molecular approaches and increasing research on HEV, it is becoming clear that HEV represents a threat for Egyptians and preventive measures should be considered to reduce the infection rate and possible complications.