Brazil has found an unlikely army to fight the buzzing villains of summer: schoolchildren armed with mosquito kits. Forget dodgeball, 1,600 students in Campo Grande spent 16 weeks raising an estimated 2.5 million mosquitoes. Yes, you read that right. The kids weren’t breeding future backyard menaces; they were nurturing Wolbachia-carrying mosquitoes, nature’s tiny disease-blocking ninjas.

Wolbachia is a harmless bacteria that makes it much harder for mosquitoes to transmit Zika, dengue, and chikungunya. The plan? Release them into the wild to mingle, mate, and pass along their anti-disease superpowers. Essentially, it’s mosquito Tinder, but for public health.

“Of course, this isn’t the silver bullet,” says Luciano Andrade Moreira, who leads Brazil’s chapter of the World Mosquito Program. “But paired with vaccines and insecticides, it’s a powerful extra weapon.”

Results are already impressive. In Yogyakarta, Indonesia, dengue cases dropped by 77 percent. Not bad for an army of kids and a swarm of good bugs.