Gates' mosquito factory in Medellin, Colombia, the largest in the world, is still operating

The official version:

"The mosquitoes produced in this factory carry bacteria called Wolbachia, which blocks their transmission to humans of dengue and other viruses such as Zika virus, chikungunya and yellow fever. By releasing them to breed with wild mosquitoes, they spread the bacteria, reducing virus transmission and protecting millions of people from disease."

These mosquitoes may be true weapons of mass destruction with the broadest spectrum of human exposure, but we just have to believe that it's all for our safety. And someone does.