title: Evolution of new genotype of West Nile virus in North America.
abstract: Previous studies of North American isolates of West Nile virus (WNV) during 1999-2005 suggested that the virus had reached genetic homeostasis in North America. However, genomic sequencing of WNV isolates from Harris County, Texas, during 2002-2009 suggests that this is not the case. Three new genetic groups have been identified in Texas since 2005. Spread of the southwestern US genotype (SW/WN03) from the Arizona/Colorado/northern Mexico region to California, Illinois, New Mexico, New York, North Dakota, and the Texas Gulf Coast demonstrates continued evolution of WNV. Thus, WNV continues to evolve in North America, as demonstrated by selection of this new genotype. Continued surveillance of the virus is essential as it continues to evolve in the New World.
authors.affiliation: University of Texas Medical Branch, Galveston, Texas 77555-0609, USA.
authors.forename: Allison R
authors.initials: AR
authors.lastname: McMullen
authors.forename: Fiona J
authors.initials: FJ
authors.lastname: May
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Hilda
authors.initials: H
authors.lastname: Guzman
authors.forename: Rudy
authors.initials: R
authors.lastname: Bueno
authors.forename: James A
authors.initials: JA
authors.lastname: Dennett
authors.forename: Robert B
authors.initials: RB
authors.lastname: Tesh
authors.forename: Alan D T
authors.initials: AD
authors.lastname: Barrett
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D002522:Chlorocebus aethiops; D019143:Evolution, Molecular; D014644:Genetic Variation; D005838:Genotype; D009656:North America; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D012641:Selection, Genetic / Q000235:genetics; D014709:Vero Cells; D014901:West Nile Fever / Q000821:virology*; D014902:West Nile virus / Q000145:classification / Q000235:genetics*
chemical_list: D012367:RNA, Viral