Surveillance and Control of Culex quinquefasciatus Using Autocidal Gravid Ovitraps

Abstract

We monitored trap captures of Culex quinquefasciatus using an interrupted time-series study to determine if autocidal gravid ovitraps (AGO traps) were useful to control the population of this mosquito species in a community in southern Puerto Rico. Data for this report came from a previous study in which we used mass trapping to control Aedes aegypti, resulting in a significant 79% reduction in numbers of this species. The AGO traps used to monitor and control Ae. aegypti also captured numerous Cx. quinquefasciatus. Culex quinquefasciatus was monitored in surveillance AGO traps from October 2011 to February 2013, followed by a mosquito control intervention from February 2013 to June 2014. Optimal captures of this mosquito occurred on the 2nd wk after the traps were set or serviced, which happened every 8 wk. Changes in collection numbers of Cx. quinquefasciatus were positively correlated with rainfall and showed oscillations every 8 wk, as revealed by sample autocorrelation analyses. Culex quinquefasciatus was attracted to and captured by AGO traps, so mass trapping caused a significant but moderate reduction of the local population (31.2%) in comparison with previous results for Ae. aegypti, possibly resulting from female mosquitoes flying in from outside of the study area and decreased attraction to the traps past the 2nd wk of trap servicing. Because Ae. aegypti and Cx. quinquefasciatus are frequently established in urban areas, mass trapping to control the former has some impact on Cx. quinquefasciatus. Control of the latter could be improved by locating and treating its aquatic habitats within and around the community.

Spatiotemporal organization of cryptic North American Culex species along an urbanization gradient

“…For example, standing irrigation waters, small containers, stormwater infrastructure and flooded subterranean concrete surfaces produced through human activity may serve as suitable ovipositional habitat for some, but not all, vector species (Norris, 2004;Townroe & Callaghan, 2014). Human-made habitats, such as insulated structures, may serve as overwintering (Arsenault-Benoit et al, 2021) or oversummering (Thareja et al, 2022) refugia that help to maintain some mosquito species in climatic regions with conditions otherwise outside of their natural thermal tolerance limits. Heterogeneity in the types and density of vegetation creates varied resting sites and habitat for vectors and their hosts, from cityscapes to parks, manicured lawns, forests or agricultural fields (Ferraguti et al, 2016;Gorris et al, 2021).…”