Endogenous Retroviruses (ERVs) represent traces of retroviral infections that fused with the genomes of their host organisms over millions of years.
Polyomaviruses constitute a family of ancient viral strains detected across diverse vertebrate species, humans included.
HBV is estimated to have infected humans for thousands of years. Although its precise age is uncertain.
HPV is another ancient virus that has likely coexisted with humans for millennia. It could have been infecting humans for tens of thousands of years.
Various members of the herpesvirus family are believed to have ancient origins and may have infected early human populations.