He bred his mosquitos in a bio-containment lab and he also used a species that's not native to the US so that even if some did escape, they'd just die off, there'd be nothing for them to mate with.
他在一个生物控制实验室繁殖蚊子， 并且蚊子也并不是美国本土的种类， 所以就算蚊子逃跑了， 也会因为没有办法交配而灭绝。