Assessment of synthetic floral-based attractants and sugar baits to capture male and female Aedes aegypti (Diptera: Culicidae)

Abstract

Background: The viruses transmitted by Aedes aegypti, including dengue and Zika viruses, are rapidly expanding in geographic range and as a threat to public health. In response, control programs are increasingly turning to the use of sterile insect techniques resulting in a need to trap male Ae. aegypti to monitor the efficacy of the intervention. However, there is a lack of effective and cheap methods for trapping males. Thus, we attempted to exploit the physiological need to obtain energy from sugar feeding in order to passively capture male and female Ae. aegypti (nulliparous and gravid) in free-flight attraction assays. Candidate lures included previously identified floral-based (phenylacetaldehyde, linalool oxide, phenylethyl alcohol, and acetophenone) attractants and an attractive toxic sugar bait-based (ATSB) solution of guava and mango nectars. A free-flight attraction assay assessed the number of mosquitoes attracted to each candidate lure displayed individually. Then, a choice test was performed between the best-performing lure and a water control displayed in Gravid Aedes Traps (GAT). Results: Results from the attraction assays indicated that the ATSB solution of guava and mango nectars was the most promising lure candidate for males; unlike the floral-based attractants tested, it performed significantly better than the water control. Nulliparous and gravid females demonstrated no preference among the lures and water controls indicating a lack of attraction to floral-based attractants and sugar baits in a larger setting. Although the guava-mango ATSB lure was moderately attractive to males when presented directly (i.e. no need to enter a trap or other confinement), it failed to attract significantly more male, nulliparous female, or gravid female Ae. aegypti than water controls when presented inside a Gravid Aedes Trap.

Ingested insecticide to control Aedes aegypti: developing a novel dried attractive toxic sugar bait device for intra-domiciliary control

“…Early field trials did not show a positive effect of ATSBs on Ae. aegypti [26,27]; however, a recent field trial in Bamako, Mali, showed promising success [31]. The principle barrier to field trial success appears to be the ability to attract Ae.…”

“…Our approach differs from most ATSB approaches in two important ways. First, we use a device with a dried sugar solution to elicit an ingestion response while other ATSBs typically use liquid sprayed on vegetation [12,15,17,26]. We hypothesize that the device is a key element in the effectiveness of DABS.…”

“…aegypti [16,24,25], semi-field and field evaluations have had poor results in reducing Ae. aegypti populations [26,27], indicating that ATSB devices must be carefully designed and tested for each target species [12].…”

Priorities for Broadening the Malaria Vector Control Tool Kit

“…Attractive toxic sugar baits (ATSBs), which utilize a mix of an oral toxin, natural sugars, and floral attractants to lure mosquitoes [33,34], take advantage of the natural propensity of both male and female mosquitoes to sugar feed. ATSBs can be used in outdoor bait stations, indoor bait stations, or can be sprayed directly onto non flowering vegetation [35–37].…”

Differential Effects of Larval and Adult Nutrition on Survival, Fecundity, and Size of the Yellow Fever Mosquito Aedes Aegypti

“…aegypti may not be as unusual as thought previously, as support for frequent sugar-feeding in certain environments has been reported [27,28], and this propensity has been used to design attractive toxic sugar baits for Ae. aegypti control [29,30]. Like larvae, adult mosquitoes may also be in uenced by nutritional stress derived from changes in food quality (e.g., sugar concentration [31]).…”