Mosquito repellents have been effective for 40 years. Now mosquitoes are learning to appreciate them

Lab tests suggest Aedes aegypti mosquitoes can learn to link DEET odor with food after repeated exposure.

More than 60% of conditioned mosquitoes moved back toward the repellent smell instead of avoiding it.

The findings complicate earlier views on repellent tolerance and show DEET must be used correctly, at the right dose and time.

If mosquitoes can associate repellent cues with feeding, some protection methods may become less effective against diseases like dengue and Zika.