Host-Feeding Patterns of Argentine Mosquitoes (Diptera: Culicidae) Collected During and after an Epizootic of Western Equine Encephalitis

Abstract

Blood meals from 277 engorged mosquitoes collected in CDC light traps during December 1982 in Santa Fe Province, Argentina, during a western equine encephalitis (WEE) epizootic were identified by precipitin test. Blood meals from 348 engorged mosquitoes collected in the same general area during February 1984 were also identified, along with blood meals from 18 engorged mosquitoes from Rio Negro Province and 58 from Chubut Province. The total of 701 mosquitoes was composed of 297 Aedes albifasciatus, 16 Ae. scapularis, 1 Anopheles albitarsis, 4 Culex (Melanoconion) delpontei, 102 Culex (Culex) spp., 99 Mansonia titillans, 15 Mansonia spp., 3 Psorophora albigenu, 6 Ps. ciliata, 4 Ps. confinnis, 50 Ps. cyanescens, 1 Ps. dimidiata, 3 Ps. discrucians, 16 Ps. pallescens, and 84 Ps. varinervis. Most of the mosquitoes (679 specimens) had fed on mammals, especially cattle; a few (19) had fed on birds. One Cx. (Mel.) delpontei had fed on an amphibian, and 2 mosquitoes contained a mixture of avian and mammalian bloods. In addition, the species composition of 20,697 mosquitoes collected in chicken-baited traps and 2,752 collected in a horsebaited trap is discussed, along with data on engorgement rates following entry of mosquitoes into the bait traps. A few mosquitoes also were collected in Nutriabaited traps (6 specimens) and in traps baited with domestic rabbits (143 specimens).