Complete coding sequence and molecular analysis of hepatitis A virus from a chimpanzee with fulminant hepatitis.

Background: Hepatitis A virus (HAV) infects both humans and non-human primates, in experimentally infected chimpanzees is typically milder than in humans. In 1982, Abe and Shikata reported a first case of a chimpanzee with fulminant hepatitis caused by spontaneous HAV infection, and the underlying mechanisms of the disease remain unknown.

Methods: To characterize denoted CFH-HAV, we conducted cloning and near full-length sequence analysis.

Results: Phylogenetic analyses of VP1-2A and complete sequence comparison between various genotypes and the sample sequence showed clustering in genotype IB. Based on BLAST analysis, the sequence was most closely related to the wild-type (HM175/WT) isolate. Amino acid and nucleic acid similarities were 99.8% and 94.41%, respectively.

Conclusions: The chimpanzee may have been infected with human HAV genotype IB. The substitutions in VP2, VP4, 2B, 2C, and 3D, which may enhance virus proliferation, contributed to disease severity culminating in fulminant hepatic failure.