Hepatitis E virus infection in Ghanaian blood donors – the importance of immunoassay selection and confirmation

Abstract

Background and Objectives Hepatitis E virus (HEV) infection is emerging as a potential new threat to blood safety after several cases of transfusion–transmission were reported from non‐epidemic countries. On the basis of seroprevalence data, HEV is endemic in Ghana where poor sanitary conditions and regular flooding are prevalent. However, no data are available for HEV prevalence in blood donors. Materials and Methods Plasma samples from 239 Ghanaian blood donors were tested for anti‐HEV IgG and IgM by ELISA (two and three assays, respectively) and Western blot (recomLine) and for HEV‐RNA by RT‐qPCR. Results All donors were RNA negative. Results from the different serological assays were discrepant: reactivity in two of the three IgM assays was correlated with elevated IgM levels, but the discrepancies between IgG assays were unrelated to the donors’ IgG levels and more likely related to assay sensitivity. Fourteen samples (5·9%) were anti‐HEV IgM reactive and 11 samples (4·6%) anti‐HEV IgG reactive in at least two serological assays from different manufacturers. Conclusions (a) In the absence of accepted confirmatory assays, it is crucial to confirm anti‐HEV reactive samples with an alternative assay, especially when the population tested carries high levels of immunoglobulin M. (b) Although asymptomatic HEV infections are common in Ghanaian blood donors, currently, it does not seem to be a major risk to blood safety.

A Comparative Study of Assay Performance of Commercial Hepatitis E Virus Enzyme-Linked Immunosorbent Assay Kits in Australian Blood Donor Samples

“…HEV serological assays have allowed seroprevalence studies, which provide useful surveillance data on the distribution of this virus, and have also assisted with identifying risk factors for exposure to HEV. However, studies have shown variability in estimates with different commercial assays [21, 28], and the results presented herein are consistent with such findings.…”

“…Studies with different commercial HEV IgG enzyme immunoassays have shown variability in sensitivity [26–28]. A study using anti-HEV reference serum (from the World Health Organisation) and including known HEV cases has shown 98% seropositivity with the Wantai IgG assay compared to 56% with the Genelabs IgG assay [27].…”

A systematic review of the epidemiology of hepatitis E virus in Africa

“…Seroprevalence varies by country from 84.3% [55] among pregnant Egyptian women aged 24 years on average to 0% among village residents aged 24 years on average in Gabon [72]. The seroprevalence seems to be higher in pregnant women than in the general population in Ghana (28.7% [78] vs. 4.6% [76]) and also in Gabon (14.2% [73] vs. 0% [72]). Two studies of Ghanaians suggest that predominant HEV genotypes in that country may be of zoonotic origin: seroprevalence among pig handlers is over 34% [75,77] whereas that among general population is about 4% [76].…”

Hospital-Based Surveillance for Viral Hemorrhagic Fevers and Hepatitides in Ghana

“…However, all PCR assays were negative, HEV immunoassays are prone to false reactivity [61], [62], and none of the patients showed both IgM and IgG. Usually, both serological markers and HEV RNA are present during acute infection ([62], [63] and validation data for the test used in this study [64]).…”