Evaluation of Aedes aegypti sugar feeding behaviour in a semi-field system in Tanzania

Abstract

Background Sugar feeding behaviour is an essential aspect for mosquito survival, fitness, reproduction, and competence. Understanding the behaviour of Aedes aegypti is a fundamental phenomenon for the development of new interventions for controlling the vectors. The objective of the current study was to investigate i) the time in an Ae. aegyptimosquito’s adult life when they are most likely to sugar feed ii) if sugar sources availability limits Ae. aegypti blood feeding with the aim of informing control strategies using attractive-targeted sugar baits (ATSBs) Methods: The preference of Ae. aegypti to feed on sugar or blood and the effect of sugar source availability on Ae. aegypti blood feeding was studied at different chronological and physiological ages in semi-field conditions in Bagamoyo, Tanzania. Experiments were done through a series of paired–choice assays whereupon mosquitoes were allowed to choose between a sugar meal or a blood meal in the form of a rabbit. Results In the first five days post emergence, Aedes aegypti mosquitoes were equally likely to opt for a sugar meal or a blood meal. However, after the first gonotrophic cycle Ae. aegypti prefer to feed on blood meal (OR=9.4; 95%CI= [6.7-13.0]; p<0.001) over a sugar meal (OR=1). Moreover, a nulliparous Ae. aegypti mosquitoes are less likely to blood feed if they have both sugar and blood sources available (OR=0.06; 95%CI [0.02-0.16] p<0.001). Conclusion In this study, sugar meal is observed to be a part of Ae. aegypti life particularly at the younger stage (nulliparous stage). Therefore, there is potential for the development of interventions such as attractive toxic sugar baits (ATSBs).