Koala retrovirus (KoRV) epidemiology varies across koala (Phascolarctos cinereus) populations with distinct differences in viral prevalence, sequence diversity, and disease impact. Curiously the more genetically restricted southern populations are less impacted by KoRV with the virus not endogenized in its replication competent form in these animals. These southern animals do, however, have replication defective recKoRV variants in their genomes indicating historical exposure to KoRV and recKoRV. Whether southern animals are inherently resistant to KoRV infection and endogenization is not clear. It is also not clear whether the current regional epidemiological patterns will persist or whether exposure to animals with infectious KoRV or cross-breeding between different genetic populations will change the KoRV prevalence with time.
Tarlinton, Rachael E. 2023. An overview of koala retrovirus epidemiology in Australia. In Proceedings of the Second Koala Retrovirus Workshop, ed. D. E. Alquezar-Planas, D. P. Higgins, C. L. Singleton, and A. D. Greenwood. Technical Reports of the Australian Museum Online 38: 3–6.