Occurrence of Tire Inhabiting Mosquito Larvae in Different Geographic Regions of West Virginia

Abstract

Eleven species of mosquito larvae were collected in 568 collection visits to 209 abandoned tire pile sites in 33 West Virginia counties from April through October of 2003. Ochlerotatus j. japonicus supplanted the native Oc. triseriatus as the most common tire-colonizing species in the state. In general, the exotic Oc. j. japonicus was a better colonizer of tires than Oc. triseriatus in peridomestic, sunlit conditions throughout the state, whereas both species were equally likely to colonize tires in nonperidomestic, shaded settings. Aedes albopictus competed effectively with Oc. triseriatus from mid-summer through October in low elevation western counties but was not well represented in central counties of the state. Aedes albopictus was seldom collected at higher elevations in eastern counties. Culex pipiens, like Ae. albopictus, was more likely to be in collections from the western portion of West Virginia throughout the study period. Frequency of occurrence of Cx. restuans peaked in early season collections and declined as the season progressed, but Anopheles punctipennis and the medically unimportant Cx. territans gradually increased in frequency each month through September. Typically, species in the genus Culex and An. punctipennis were predisposed to peridomestic, sunlit habitats. Larvae of the predatory Toxorhynchites rutilus septentrionalis were found mostly in nonperidomestic, shaded settings. This species initially appeared in mid-summer, and by August and September it was found in as many as 30% of the collection sites in western and eastern counties. Larvae of An. barberi, Oc. atropalpus, and Orthopodomyia signifera were poorly represented in collections.

Environmental Correlates of Abundances of Mosquito Species and Stages in Discarded Vehicle Tires

“…For instance, human population density positively affected almost all Culex (Figs. 1 and 2), a result reflecting the fact that all of these Culex species are peridomestic (Vinogradova 2000, Joy et al 2003, Joy 2004, Costanzo et al 2005, Joy and Sullivan 2005. Unexpectedly, we found populations of Ae.…”

“…atropalpus and Ae. triseriatus were more likely to be found in sites with lower human populations, as both species are thought to be nonperidomestic (Joy et al 2003, Joy 2004, Joy and Sullivan 2005. Sites where Aedes were more common also tended to be rural and near forests (Fayette and Effingham counties, Table 1), which might explain why plantderived detritus (Table 2) was the most important factor in explaining their patterns of occurrence ( Figs.…”

La Crosse Virus Field Detection and Vector Competence of Culex Mosquitoes

“…in West Virginia was 0.4 (95% CL = 0.2-0.9) infected mosquitoes per 1,000 specimens. 49 LACV-positive Culex mosquitoes were collected in urban and peridomestic habitat 30 in the Central Allegheny plateau (Kanawha County), Ohio River lowland (Jackson and Cabell Counties), and the Alleghany highlands (Berkeley County).…”

“…RT-PCR targeting the M segment of LACV was conducted with the QuantiTect probe RT-PCR Kit (Qiagen) using two primer-probe sets (Table 1). We present the threshold cycle (C T ), defined as the amplification cycle at which the fluorescence increased above the threshold value (i.e., crossing point cycle 30 Samples were collected weekly from counties with high (Nicholas, Fayette, and Raleigh) and low human incidence of LACV (Kanawha, Jackson, and Wood) as previously defined.…”

“…restuans mosquitoes, dominant over Cx. pipiens in southwestern Virginia and West Virginia, 30,31 are more efficient vectors when larvae are resource limited. After a minimum of 24-hour storage in a −80°C freezer, mosquitoes were identified and pooled into groups of up to 50 females by species, collection site, and date.…”