Hepatitis E virus infection in the Irish blood donor population.

<bold>Background: </bold>Hepatitis E virus (HEV) Genotype 3 (G3) infection is a zoonosis that may be transmitted during the acute phase by transfusion. The aim of this study was to determine the incidence of HEV and seroprevalence among Irish blood donors.<bold>Study Design and Methods: </bold>Anonymized samples from 1076 donations collected in 2012 were tested for HEV immunoglobulin (Ig)G using the Wantai enzyme-linked immunosorbent assay. A total of 24,985 anonymized donations collected between December 2013 and June 2014 were individually tested for HEV RNA using the Procleix HEV assay; reactive donations were confirmed by an in-house real-time polymerase chain reaction (PCR) test.<bold>Results: </bold>Seroprevalence for anti-IgG was 5.3% (95% confidence interval [CI], 4.0%-6.8%), ranging from 1.1% in the 18- to 29-years age group to 33.3% in males over 60 years. HEV RNA screening of 24,985 samples yielded five PCR-confirmed donations (1:4997, 0.02%; 95% CI, 0.0065%-0.0467%), only one of which was serologically reactive (HEV IgM reactive only). Viral loads ranged from 10 to 44,550 IU/mL. Genotype analysis on three samples identified HEV G3 virus. Four of the five viremic donations were from donors in the 18- to 29-years age group (p = 0.01).<bold>Conclusion: </bold>Seroprevalence for anti-HEV IgG was low compared to some European countries, but 1 in 5000 donations was viremic. Viremia was predominantly in younger Irish donors. After Department of Health approval the Irish Blood Transfusion Service implemented individual blood donation HEV RNA screening initially for a 3-year period from January 2016. [ABSTRACT FROM AUTHOR]