In this video, a man partially immerses a praying mantis in water, thereby forcing the hairworms possessing it to leave. That the mantis also dies, according to one commenter, is not because the videomaker left it in the water to drown alongside the infestors. [via]
The worm digested the insides of the Praying Mantis. While inside, it keeps the nervous system from collapsing, but upon existing the Mantis immediately dies. So the Mantis isn't dead yet at the start of this video, its close to being a zombie, so not really alive either.