With over 40 percent of the world's population at risk from dengue fever, according to the World Health Organization (WHO), scientists are embracing a novel way of preventing the infection that sickens 50 million-100 million people every year.
One of the most common ways to prevent the spread of dengue fever -- a virus-caused disease spread by mosquitoes -- is to spray cities that have a high concentration of it with pesticides.
The problem, obviously, is that the potentially toxic pesticides are sprayed where the bugs and people live. And it's not always effective; mosquitoes quickly build up immunity to the chemicals.
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Recently, though, scientists have begun experimenting with fighting mosquitoes with mosquitoes. By genetically modifying the bugs so that they either can't produce offspring or produce offspring that die quickly, the population falls.
So far, the technique has been tested with dengue fever in Malaysia and the Cayman Islands. This year Brazil is releasing genetically modified mosquitoes.
"In Brazil and the Cayman, dengue is very prevalent, and the people have a high awareness of the disease, and we have great receptivity for what we are trying to do," Oxitec CEO Hadyn Parry told TIME.
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Similar strategies have been used to curb malaria, another mosquito-borne disease that caused approximately 655,000 deaths in 2010, according to the WHO.
But Greenpeace and others warn that genetically modified insects could lead to unknown issues in the wild, including the chance of dengue fever mutating into a new disease.