Evidence for co-evolution of West Nile Virus and house sparrows in North America.

• Published in: PLoS Neglected Tropical Diseases
• Main Authors: Nisha K Duggal, Angela Bosco-Lauth, Richard A Bowen, Sarah S Wheeler, William K Reisen, Todd A Felix, Brian R Mann, Hannah Romo, Daniele M Swetnam, Alan D T Barrett, Aaron C Brault
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2014
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic
• Online Access: https://doi.org/10.1371/journal.pntd.0003262; https://doaj.org/article/c07ce7b8df0c4363b2338c93043c7885

West Nile virus (WNV) has been maintained in North America in enzootic cycles between mosquitoes and birds since it was first described in North America in 1999. House sparrows (HOSPs; Passer domesticus) are a highly competent host for WNV that have contributed to the rapid spread of WNV across the U.S.; however, their competence has been evaluated primarily using an early WNV strain (NY99) that is no longer circulating. Herein, we report that the competence of wild HOSPs for the NY99 strain has decreased significantly over time, suggesting that HOSPs may have developed resistance to this early WNV strain. Moreover, recently isolated WNV strains generate higher peak viremias and mortality in contemporary HOSPs compared to NY99. These data indicate that opposing selective pressures in both the virus and avian host have resulted in a net increase in the level of host competence of North American HOSPs for currently circulating WNV strains.