Comparison of Mosquito Trapping Method Efficacy for West Nile Virus Surveillance in New Mexico

Abstract

As part of the West Nile virus surveillance program for the state of New Mexico, 13 sites along the Rio Grande River were sampled for mosquitoes during spring and summer 2003. We evaluated 3 different trapping procedures for their effectiveness at capturing selected species of mosquitoes. The 3 methods used were a dry ice-baited Centers for Disease Control and Prevention (CDC) light trap set 1.5 m above the ground (standard method), a CDC light trap suspended within the forest canopy, and a gravid trap set on the ground. Thirteen sites were sampled for 10 1-night periods biweekly from May through September. The relative numbers of captured Culex tarsalis, Cx. salinarius, Cx. quinquefasciatus, and Aedes vexans as well as the numbers of total recorded captures of all species were compared for each trapping method. Significant differences were observed for each species by location and by trapping method. Culex tarsalis was most commonly caught in canopy or standard CDC traps, especially in cottonwood bosque. Culex salinarius was found most frequently in association with marshy water, and was most often caught in gravid or standard light traps. Culex quinquefasciatus was captured almost exclusively in gravid traps within urban areas. Aedes vexans was primarily sampled in standard CDC light traps and found most frequently in wooded areas near floodplains. With the exception of Cx. Quinquefasciatus, no species was collected significantly more frequently in gravid or canopy traps than in the standard CDC light trap. Our findings do not support altering the methods currently used in New Mexico, namely, the use of 1.5-m CDC light traps and gravid traps. An increased use of gravid traps seems to be warranted in monitoring urban vector populations (specifically Cx. quinquefasciatus and Cx. salinarius) that may be involved in human transmission.

Winter Activity and Aboveground Hybridization Between the Two Biotypes of the West Nile Virus VectorCulex pipiens

“…It is likely that a fraction of the typical underground biotype molestus habitats was not sampled, such as water collection basins in the subway (Reusken et al 2010a). In addition to a bias in sampling of the larval populations, habitat characteristics and environmental conditions at trapping locations could have influenced the number and composition of collected adult mosquitoes (DiMenna et al 2006, Giberson et al 2007). An alternative explanation could be that biotype pipiens larvae are better competitors and, therefore, can outcompete biotype molestus larvae.…”

A novel window entry/exit trap for the study of endophilic behavior of mosquitoes

“…However, many of the important vector species carrying malaria, filariasis, arboviruses and other pathogens are endophilic and so for epidemiological studies, samples of subpopulations such as blood fed females, those old enough to vector pathogens, and males closely associated with them might be more desirable than sampling the mosquito population as a whole (Bradley et al, 1949; Akiyama, 1973; Dimena et al, 2006). Indoor sampling is usually performed with different types of manual and battery powered aspirators, light traps, hand nets, and pyrethrum spray catches (PSC), while mosquitoes moving either in or out of houses are traditionally collected with different types of entrance and exit traps (WHO, 1975; Silver 2008).…”

Evaluation of Seasonal Feeding Patterns of West Nile Virus Vectors in Bernalillo County, New Mexico, United States: Implications for Disease Transmission

“…tarsalis appears to feed regularly on both avian and mammalian hosts (Greenberg et al 2012, 2013). These three species were selected for analysis because all three have tested positive for the West Nile virus (WNV) in Bernalillo County, NM, and have been implicated as potential vectors of this arbovirus (DiMenna et al 2006a). All three of these species have been judged to be competent WNV vectors (Turell et al 2001, Cupp et al 2004, Kilpatrick et al 2005, Molaei and Andreadis 2006, DiMenna 2006b), and the roles of both Cx.…”