RESUMEN
The accumulation and fixation of mutations in West Nile virus (WNV) led to the emergence of a dominant genotype throughout North America. Subsequent analysis of 44 isolates, including 19 new sequences, from Houston, Texas, suggests that WNV has reached relative genetic stasis at the local level in recent years.
Asunto(s)
Enfermedades de las Aves/virología , Aves/virología , Culex/virología , Evolución Molecular , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/clasificación , Virus del Nilo Occidental/genética , Animales , Enfermedades de las Aves/epidemiología , Genotipo , Halcones/virología , Datos de Secuencia Molecular , Mutación , Passeriformes/virología , Filogenia , Análisis de Secuencia de ADN , Texas/epidemiología , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/virologíaRESUMEN
West Nile virus (WNV) was detected in 11 dead birds and two mosquito pools collected in east Texas and southern Louisiana during surveillance studies in the winter of 2003 to 2004. These findings suggest that WNV is active throughout the year in this region of the United States.
Asunto(s)
Enfermedades de las Aves/epidemiología , Estaciones del Año , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/aislamiento & purificación , Animales , Enfermedades de las Aves/virología , Culex/virología , Insectos Vectores/virología , Louisiana/epidemiología , Control de Mosquitos , Passeriformes/virología , Texas/epidemiología , Factores de Tiempo , Fiebre del Nilo Occidental/epidemiologíaRESUMEN
Harris County, Texas, is an endemic area of St. Louis encephalitis (SLE); and an active surveillance program that monitors SLE virus activity in mosquitoes, birds, and humans has been in place there for the past 28 years. In June of 2002, West Nile (WN) virus appeared in Houston and quickly spread throughout the region. This report describes the results of 12 years of SLE surveillance in Harris County and the contrasting pattern of WN virus activity, when it arrived in 2002. Our data indicate that both SLE and WN viruses can coexist, despite their ecologic, antigenic, and genetic similarities, and that both viruses will probably persist in this geographic region.