Rapid assessment of mosquitoes and arbovirus activity after floods in southeastern Kansas, 2007.

Abstract A rapid assessment was conducted in July–August 2007 to determine the impact of heavy rains and early summer floods on the mosquitoes and arbovirus activity in 4 southeastern Kansas counties. During 10 days and nights of collections using different types and styles of mosquito traps, a total of 10,512 adult female mosquitoes representing 29 species were collected, including a new species record for Kansas (Psorophora mathesoni). High numbers of Aedes albopictus were collected. Over 4,000 specimens of 4 Culex species in 235 species-specific pools were tested for the presence of West Nile, St. Louis, and western equine encephalitis viruses. Thirty pools representing 3 Culex species were positive for West Nile virus (WNV). No other arboviruses were detected in the samples. Infection rates of WNV in Culex pipiens complex in 2 counties (10.7/1,000 to 22.6/1,000) and in Culex salinarius in 1 county (6.0/1,000) were sufficiently high to increase the risk of transmission to humans. The infection rate of ...