Hepatitis E virus persists in the ejaculate of chronically infected men

Background & Aims Hepatitis E virus (HEV) infections are prevalent worldwide. Various viruses have been detected in the ejaculate and can outlast the duration of viremia, indicating replication beyond the blood-testis barrier. HEV replication in diverse organs, however, is still widely misunderstood. We aimed to determine the occurrence, features and morphology of HEV in the ejaculate. Methods Presence of HEV in testis was assessed in 12 experimentally HEV-genotype-3 infected pigs. We further tested ejaculate, urine, stool and blood from 3 chronically HEV-genotype-3 infected and 6 immunocompetent patients with acute HEV infection by HEV-PCR. Morphology and genomic characterization of HEV particles from various human compartments were determined by HEV-PCR, density gradient measurement, immune-electron microscopy and genomic sequencing. Results In 2 of the 3 chronically HEV-infected patients, we observed HEV-RNA (genotype-3c) in seminal plasma and semen with viral loads >2 logs higher than in the serum. Genomic sequencing showed significant differences between viral strains in the ejaculate compared to stool. Under ribavirin-treatment, HEV shedding in the ejaculate outlasted duration of viremia for >9 months. Density gradient measurement and immune-electron microscopy characterized (enveloped) HEV particles in the ejaculate as intact. Conclusions The male reproductive system was shown to be a niche of HEV persistence in chronic HEV infection. Surprisingly, sequence analysis revealed distinct genetic HEV variants in the stool and serum, originating from the liver, compared to variants in the ejaculate originating from the male reproductive system. Enveloped HEV particles in the ejaculate did not morphologically differ from serum derived HEV particles.