Breeding Kamikaze Mosquitoes
(Inside Science TV) -- One of the deadliest forces on earth is the humble mosquito. Mosquito-borne diseases like malaria, chikungunya, yellow fever and West Nile virus infect more than 350 million people and kill another 1 million people every year.
Now, scientists in Florida hope to wipe out some of these deadly diseases by genetically modifying their winged carriers.
"Mosquitoes are probably the most dangerous animal in the world. More people are killed by them [than] by anything else," said Michael Doyle, an entomologist at the Florida Keys Mosquito Control District in Key West, Florida.
To help control the mosquito population, Doyle is concentrating on fighting the Aedes aegypti mosquito that spreads dengue fever.
His team fights them with one of the most advanced spraying systems in the world.
"W're using a non-toxic bacteria and we're spraying from the air with one of the helicopters," Doyle said.
The spray is effective but has only reduced the mosquito population by 50 percent. Now, researchers want to improve the rate with genetically modified mosquitoes.
"Because you're just going after one species, it doesn't affect the other species in the environment," said Doyle.
This technique works by locally introducing mosquitos that have a particular genetic modification into the existing mosquito population. In this case, the male mosquitos are genetically modified with a gene that causes their offspring to die shortly after hatching. The researchers think this modification could wipe out the Aedes aegypti population in the Florida Keys in eight months.
This particular strategy of essentially sterilizing male mosquitos is already being used successfully in Brazil, with a more than 90 percent reduction in population.
"If you eliminate the species you eliminate all the diseases it could potentially carry," said Doyle.
U.S. Food and Drug Administration tests will make sure it's safe to release the modified mosquitoes. Scientists are hopeful they could be buzzing around the U.S. as early as next year.
The Florida Keys has not had a case of dengue fever in three years. But unlike spraying, which kills all types of mosquitoes and insects, by using the sterilization technique, only the mosquitoes they are targeting are killed. In this case, Aedes aegypti is not native to the Florida Keys, but there are 42 other types of mosquitoes that are.
