High prevalence of TT virus (TTV) in naive chimpanzees and in hepatitis C virus-infected humans: frequent mixed infections and identification of new TTV genotypes in chimpanzees

A recently discovered DNA virus, TT virus (TTV), is prevalent in humans. In the present study, the genetic heterogeneity of TTV was evaluated in hepat itis C virus (HCV)-infected patients and in chimpanzees. rm DNA was detecte d by PCR in serum samples from all ten HCV-infected patients studied; at le ast five major TTV genotypes, all previously identified in humans, were rec overed. Eight patients were infected with multiple variants of Till. TTV DN A was detected by PCR in serum samples from 11 (65%) of 17 naive chimpanzee s bred in captivity; a persistent infection was present in three of six ani mals. At least five chimpanzees were infected with more than one TTV varian t. Detection of TTV DNA in chimpanzee faecal samples suggests the possibili ty of faecal-oral transmission. Phylogenetic analysis of ORF1 sequences amp lified from chimpanzees identified three major genotypes which had not prev iously been recognized in humans.