Epidemiology, genetic diversity, and evolution of endemic feline immunodeficiency virus in a population of wild cougars.


Journal Article

Within the large body of research on retroviruses, the distribution and evolution of endemic retroviruses in natural host populations have so far received little attention. In this study, the epidemiology, genetic diversity, and molecular evolution of feline immunodeficiency virus specific to cougars (FIVpco) was examined using blood samples collected over several years from a free-ranging cougar population in the western United States. The virus prevalence was 58% in this population (n = 52) and increased significantly with host age. Based on phylogenetic analysis of fragments of envelope (env) and polymerase (pol) genes, two genetically distinct lineages of FIVpco were found to cooccur in the population but not in the same individuals. Within each of the virus lineages, geographically nearby isolates formed monophyletic clusters of closely related viruses. Sequence diversity for env within a host rarely exceeded 1%, and the evolution of this gene was dominated by purifying selection. For both pol and env, our data indicate mean rates of molecular evolution of 1 to 3% per 10 years. These results support the premise that FIVpco is well adapted to its cougar host and provide a basis for comparing lentivirus evolution in endemic and epidemic infections in natural hosts.

Full Text

Cited Authors

  • Biek, R; Rodrigo, AG; Holley, D; Drummond, A; Anderson, CR; Ross, HA; Poss, M

Published Date

  • September 2003

Published In

Volume / Issue

  • 77 / 17

Start / End Page

  • 9578 - 9589

PubMed ID

  • 12915571

Pubmed Central ID

  • 12915571

Electronic International Standard Serial Number (EISSN)

  • 1098-5514

International Standard Serial Number (ISSN)

  • 0022-538X

Digital Object Identifier (DOI)

  • 10.1128/JVI.77.17.9578-9589.2003


  • eng