D3330: Impact of mass trapping against Culex quinquefasciatus

Aedes aegypti and Culex quinquefasciatus mosquitoes overlap in tropical urban areas to varying degrees. Studies using mass trapping against Ae. aegypti in Puerto Rico have shown both significant reductions in the number of female mosquitoes and arbovirus transmission. Autocidal Gravid Ovitraps (AGO traps) used to monitor and control Ae. aegypti also captured numerous gravid females of Cx. quinquefasciatus. We report on the changes in the population of Cx. quinquefasciatus in an interrupted-time series study primarily aimed at controlling Ae. aegypti in a community in southern Puerto Rico (pre-intervention: October 2011 – February 2013; post-intervention: February 2013 – June 2014). Results showed a significant 31.2% reduction of Cx. quinquefasciatus in comparison with the reported reduction of 79% of Ae. aegypti. There was also a significant positive association between rainfall and captures of Cx. quinquefasciatus. The highest trap yields of this mosquito occurred on the second week after trap setting or refreshment, likely because of the stimuli derived from the decomposition of the hay pack inside the trap. Thus, these results showed that mass trapping against Ae. aegypti also caused reductions of Cx. quinquefasciatus in the study area.