29520800

PMC5912996

Background

Reported hepatitis E virus (HEV) antibody assay performance characteristics are variable. Using a subset of surplus US blood donation samples, we compared assays for detecting anti-HEV IgM and IgG or total anti-HEV antibodies.

Methods

Samples from 5040 random blood donations, all HEV-RNA negative, collected primarily in the Midwestern US in 2015 were tested for anti-HEV IgM and IgG or total anti-HEV using assays manufactured by Diagnostic Systems, Wantai and MP Biomedicals.

Results

Overall, percent detection for anti-HEV IgG and total anti-HEV was 11.4%, and for anti-HEV IgM was 1.8%. Nine samples were reactive for anti-HEV IgM by all assays giving a recent infection rate of 0.18%. Anti-HEV IgG/total anti-HEV detection rates increased with age. Inter-assay agreement was higher among the IgG anti-HEV/total anti-HEV assays (84%) than the IgM assays (22%). Regression analyses of signal-to-cutoff ratios from IgG/total antibody assay were heteroskedastic indicating no constant variance among these assays suggesting they may detect different epitopes, or were affected by waning or less avid antibodies in the US donor population.

Conclusions

Although similar percentages of IgG anti-HEV/total anti-HEV detection were observed across the three commercial assays, each assay detected a unique sample subpopulation and were heteroskedastic when compared pairwise. Discordance was higher among anti-HEV IgM assays, but a recent HEV infection rate of at least 0.18% was estimated based on assay concordance.

CDC Public Access

CC999999/ImCDC/Intramural CDC HHS/United States