A NEW VARIANT OF HEPATITIS A VIRUS CAUSING TRANSIENT LIVER ENZYME ELEVATIONS IN MAURITIUS-ORIGIN LABORATORY-HOUSED CYNOMOLGUS MACAQUES

Mecklenburg, L.; Ducore, R.; Boyle, M.; Newell, A.; Boone, L.; Luft, J.; Romeike, A.; Haverkamp, A.-K.; Mansfield, K.; Baczenas, J.; Minor, N.; O'Connor, S. L.; O'Connor, D. H.

doi:10.1101/2022.11.18.515766

bioRxiv · 10.1101/2022.11.18.515766

A NEW VARIANT OF HEPATITIS A VIRUS CAUSING TRANSIENT LIVER ENZYME ELEVATIONS IN MAURITIUS-ORIGIN LABORATORY-HOUSED CYNOMOLGUS MACAQUES

Mecklenburg, L.·Ducore, R.·Boyle, M.·Newell, A.·Boone, L.·Luft, J.·Romeike, A.·Haverkamp, A.-K.·Mansfield, K.·Baczenas, J.·Minor, N.·O'Connor, S. L.·O'Connor, D. H.

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Abstract

Hepatitis A virus (HAV) infects humans and non-human primates causing an acute self-limited illness. Three HAV genotypes have been described for humans and three genotypes have been described for non-human primates. We observed transiently elevated liver enzymes in Mauritius-origin laboratory-housed macaques in Germany and were not able to demonstrate HAV by serology and PCR. Using deep sequencing, we have identified a new HAV genotype with 86% nucleotide sequence homology to HAV genotype IV capsid proteins and approximately 80% nucleotide homology to other HAV genotypes. In situ hybridization indicates persistence in the biliary epithelium up to 3 months after liver enzymes were elevated. Vaccination using a commercial vaccine against human HAV prevented reoccurrence of liver enzyme elevations. Since available assays for HAV did not detect this new variant, knowledge of its existence may ameliorate potential significant epidemiological and research implications in laboratories globally. Article Summary LineA new genotype of hepatitis A virus, that was not identifiable by available diagnostic assays, caused liver enzyme elevations in laboratory-housed Mauritius-origin Cynomolgus macaques.

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Mecklenburg, L., Ducore, R., Boyle, M., Newell, A., Boone, L., Luft, J., Romeike, A., Haverkamp, A.-K., Mansfield, K., Baczenas, J., Minor, N., O'Connor, S. L., O'Connor, D. H.. 2022-11-18. A NEW VARIANT OF HEPATITIS A VIRUS CAUSING TRANSIENT LIVER ENZYME ELEVATIONS IN MAURITIUS-ORIGIN LABORATORY-HOUSED CYNOMOLGUS MACAQUES. https://doi.org/10.1101/2022.11.18.515766

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