Although Hepatitis C Virus was discovered more than 20 years ago, its origins remain obscure largely because no closely related animal virus had been identified. Until very recently Hepatitis C Virus was considered the only member of the genus hepacivirus (a name concocted from words ‘hepatitis’, ‘c’ and ‘virus’).
Most medical textbooks still mention this outdated information, because now we should be aware that related viruses have been discovered in dogs (Canine Hepatitis C Virus), horses (Equine Hepatitis C Virus), bats (GB Virus-B) and some rodents (Rodent Hepatitis C Virus).
Three highly divergent rodent clades of Hepatitis C Virus were detected in 27 European bank voles (Myodes glareolus) and 10 in South African four-striped mice (Rhabdomys pumilio). Which means that the virus probably has a worldwide distribution.
It shows that Hepatitis C Virus, like other potentially deadly viruses, has the ability to infect multiple species, jump species barriers, evolve, mutate and adapt. It is an worrying idea that Hepatitis C Virus might change enough to infect us again and again.
 Kapoor et al: Characterization of a canine homolog of hepatitis C virus in Proceedings of the National Academy of Sciences - 2011
 Burbelo et al: Serology-Enabled Discovery of Genetically Diverse Hepaciviruses in a New Host in Journal of Virology - 2012
 Quan et al: Bats are a major natural reservoir for hepaciviruses and pegiviruses in Proceedings of the National Academy of Sciences - 2013
 Drexler et al: Evidence for novel hepaciviruses in rodents in PLos Pathogens - 2013