Actually Microbes,parasites, bacteria, and viruses don't "prey" on us, they exist in us like we exist in the planet, and like how we used the earths rotation to fly to the moon. We are host, but they aren't "preying on us". Preying would be them deliberately hunting mankind out to extinction, and they have never mounted a large scale assault on mankind. There have been outbreaks of certain diseases, but all those microbes etc. use us like we use the planet. We drill for oil, dig up and explode huge areas of land, we cut down entire forests, but we aren't preying on the planet. One day we may be able to fly to other planets and then we will colonize them and begin the process we have here, domesticate animals, mine and collect resources, in habit until it is unusable. That's what microbes etc. do, they all use us to live and reproduce on, there are many microbes, parasites, viruses and shit that are in us right now and aren't hurting us at all! Some hurt us, some don't. In other words, Thoth-Amon, despite our shared interest in Robert E. Howards Literature, you're incorrect.
@ the guy above Thoth - to long; didn't read.