Impact on Aedes aegypti Mosquitoes Exposed to Honey-Impregnated Flinders Technology Associates (FTA®) Cards

Abstract

Programs to control viruses transmitted by mosquitoes requires the implementation of surveillance tools. Over the past decade, Flinders Technology Associates (FTA^®) cards, which preserve nucleic acids, have emerged as an innovating surveillance system for collecting arboviruses expectorated during mosquito sugar feeding. In this study, we evaluate the survival rates of two strain of Aedes aegypti (New Orleans (NO) and Cayenne (CAY)) in the laboratory after exposing to either honey-impregnated FTA^® cards or untreated filter paper (UFP) card. Experimental exposure of mosquitoes to FTA^® cards during sugar feeding significantly negatively impacted their survival, as compared to untreated filter paper. The median survival time was 2 days (95% confidence interval [CI] 1 day, 3 days) for mosquitoes exposed to FTA cards from strain NO and 3 days (95% CI 2 days, 3 days) for mosquitoes exposed to FTA cards from strain CAY. Mosquitoes exposed to UFP did not survive until the end of the experiment (4 days for strain NO and 7 days for strain CAY). Although this finding does not preclude the use of FTA^® cards in surveillance, it is crucial to consider and incorporate this factor into study designs.

Keywords: Aedes aegypti; FTA® cards; arboviruses; blotting paper; sugar feeding; surveillance.

Figure 1

Kaplan–Meier curves representing survival probability estimates for mosquitoes orally exposed to FTA^® and UFP cards for sugar feeding. Survival curves and corresponding risk tables are shown by condition only with 95% confidence intervals in light shading for CAY strain (A) or NO strain (B). A log-rank test was used to compare survival times of mosquitoes experimentally exposed to FTA^® and UFP cards.