Medical researchers have discovered that an inexpensive deworming pill that has been used in Africa for more than 25 years can kill mosquitoes. The medicine, known as ivermectin, is effective for only a month. So it's necessary for everyone in a region to take it at the same time. But when administered that way, the incidence of malaria can drop by 80%:

They vacuumed mosquitoes from the walls of huts in three villages whose inhabitants had recently been given ivermectin and three whose had not, and tested to see how many mosquitoes contained malaria parasites.

The ivermectin villages had almost 80 percent fewer.

The drug was shortening the mosquitoes’ lives, explained the lead author, Brian D. Foy, a Colorado State mosquito expert. Only older insects transmit malaria, since they must get it from humans first.

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