Laboratory bioassay to compare susceptibilities of Aedes aegypti and Anopheles albimanus to Bacillus thuringiensis var. israelensis as affected by their feeding rates.

This study presents the effect of differences in the feeding rates of Aedes aegypti and Anopheles albimanus on their susceptibilities to Bacillus thuringiensis israelensis. Aedes aegypti was more susceptible than An. albimanus because of its faster rate of feeding. Aedes aegypti ingested 11.5 times more spores than did An. albimanus, resulting in lower LT50 values. Anopheles albimanus larvae fed at a slower rate and required fewer spores than Ae. aegypti to induce 50% mortality. These findings support earlier reports of much higher concentrations of B. thuringiensis required to kill various anopheline species.