Environmental influences on Aedes aegypti catches in Biogents Sentinel traps during a Californian “rear and release” program: Implications for designing surveillance programs

Abstract

As Aedes aegypti continues to expand its global distribution, the diseases it vectors (dengue, Zika, chikungunya and yellow fever) are of increasing concern. Modern efforts to control this species include "rear and release" strategies where lab-reared mosquitoes are distributed throughout the landscape to replace or suppress invasive populations. These programs require intensive surveillance efforts to monitor their success, and the Biogents Sentinel (BGS) trap is one of the most effective tools for sampling adult Ae. aegypti. BGS trap catches can be highly variable throughout landscapes, so we investigated the potential impacts of environmental factors on adult Ae. aegypti capture rates during a "rear and release" program in California to better understand the relative contributions of true variability in population density across a landscape and trap context. We recorded male and female Ae. aegypti catches from BGS traps, with and without CO 2 , throughout control sites where no mosquitoes were released and in treatment sites where males infected with Wolbachia were released. BGS trap catches were positively influenced by higher proportions of shade or bushes in the front yard of the premises as well as the presence of potential larval habitats such as subterranean vaults. In contrast, an increase in residential habitat within a 100 m radius of trap locations negatively influenced BGS trap catches. For male Ae. aegypti, increased visual complexity of the trap location positively influenced capture rates, and the presence of yard drains negatively affected catch rates in control sites. Lastly, for BGS traps using CO 2 , higher catch rates were noted from traps placed greater than one meter from walls or fences for both male and female mosquitoes. These results have important implications for surveillance programs of Ae. aegypti throughout the Californian urban environment including adult monitoring during "rear and release" programs.

The Effect of Sound Lure Frequency and Habitat Type on Male Aedes albopictus (Diptera: Culicidae) Capture Rates With the Male Aedes Sound Trap

“…For optimizing MAST placement, future studies should investigate environmental factors important in influencing catch (e.g., amount of shade, vegetation type, and distance to households) with both the MAST and the BGS trap, as has been undertaken for optimizing BGS trap catches of Ae. aegypti following ‘rear and release’ programs ( Staunton et al 2019b , 2020a ).…”

“…Within a landscape, the abundance of mosquitoes are naturally highly heterogeneous ( Burkot et al 2018 , Staunton et al 2020a ). Fine-scale variations in mosquito abundance is likely driven by a combination of factors including microclimate ( Murdock et al 2017 ) and environmental factors ( Staunton et al 2019b , 2020a ).…”

“…Within a landscape, the abundance of mosquitoes are naturally highly heterogeneous ( Burkot et al 2018 , Staunton et al 2020a ). Fine-scale variations in mosquito abundance is likely driven by a combination of factors including microclimate ( Murdock et al 2017 ) and environmental factors ( Staunton et al 2019b , 2020a ). Understanding fine-scale variations in vector abundance is essential for effectively targeting vector control operations, such as vegetation barrier sprays ( Li et al 2010 , Muzari et al 2017 ) and also for understanding the fine-scale risk of mosquito exposure to residents.…”

Evaluation of the New Modular Biogents BG-Pro Mosquito Trap in Comparison to CDC, EVS, BG-Sentinel, and BG-Mosquitaire Traps

“…The increasing effort to seek nonchemical pesticide control measures for mosquitoes has led to the application of sterile insect techniques (SIT) with mass release of males sterilized by irradiation, infected with Wolbachia or modified genetically (O'Connor et al 2012, Carvalho et al 2015, Bellini et al 2021). An efficient monitoring of male mosquitoes is crucial for SIT projects to assess survival, dispersal, longevity, and the ratio of SIT to wild males (Alphey 2002, Carvalho et al 2015, Bouyer et al 2020, Staunton et al 2020. Currently, the BG Sentinel is often used for monitoring populations of male Aedes mosquitoes (Bouyer et al 2020;Staunton et al 2020Staunton et al , 2021.…”

Impact of visual features on capture of Aedes aegypti with host decoy traps (HDT)

“…Although male Ae. aegypti do not exhibit host‐seeking drives, their ability to navigate towards a target has been shown to be influenced by a similar set of stimuli, including a positive correlation with the visual complexity of the target's environment (Staunton et al ., 2020).…”