Comparison of sampling efficacy of sweeping and dipping for Aedes aegypti larvae in tires.

A sweep net with a flexible plastic frame was compared to a dipper for sampling efficacy for Aedes aegypti larvae in different-sized tires. When known numbers of mosquito larvae were introduced into tires, from 2 to 6.8 times more larvae were recovered by sweeping than by dipping. Sediment in the tires significantly reduced the recovery of larvae by both methods. Sampling efficacy was affected by water level and tire size. In relation to dipping, sweeping showed less variation in percentage recovery, higher sensitivity for detecting larvae and had better correlations with known numbers of larvae in tires. We conclude that sweeping is superior to dipping for sampling mosquito larvae in tires.