Following ingestion, the parasporal crystals are solubilized in the alkaline larval midgut, followed by proteolytic activation of the soluble insecticidal crystal proteins. The toxin binds to a receptor on the midgut cell wall resulting in pore formation in the cell, which leads to death of the larva. Bacillus thuringiensis var. israelensis treated mosquito larvae generally cease feeding
within 1 hour, show reduced activity by two hours, extreme sluggishness by four hours and general paralysis by six hours
after ingestion