| Participant: | McMullen, Allison |
THE MOLECULAR EPIDEMIOLOGY OF WEST NILE VIRUS IN HARRIS COUNTY, TX FROM 2002-2008
Allison R. McMullen, M.S.1, F. May, Ph.D. 1, R.B. Tesh, M.D. 1 and A.D.T. Barrett, Ph.D. 1, 2
1Department of Pathology and 2Sealy Center for Vaccine Development, UTMB
Background: West Nile virus (WNV) is a member of the Flaviviridae family in the genus Flavivirus and can cause disease in humans ranging from a mild fever to severe neurological disease. Since its introduction to the United States in 1999, WNV has spread throughout North America, and the virus "arrived" and has remained in Texas since 2002. Objective: The objective of this project is to examine the genetic and phenotypic variation in the WNV in Houston, TX, in order to investigate the evolution of WNV in the United States. Methods: Nucleotide and deduced amino acid sequence was investigated and compared for 53 isolates from Harris County between 2002 and 2008, and these isolates were compared to other isolates from around the United States. Phylogenetic analyses were conducted using the whole genome sequence and the prM/E genes from the 2002-2008 Harris County isolates. Results: At present, there have been 29 unique nucleotide changes in a 2007 WNV isolate compared to isolates from 1999-2004 with 4 unique amino acid substitutions of interest (M-30, NS2A-80, NS3-562 and NS4A-85). The substitutions in NS2A, NS3 and NS4 have occurred since 2004 and the substitution in the M protein appears to have occurred between 2006 and 2007. Conclusion: WNV continues to evolve in Southeast Texas and the potential effects of the nucleotide changes on the phenotype of WNV are being investigated. Supported by NIH.