Of course they dont, but they also not always stay hidden.

Dont sit around and do nothing waiting for death. Grab a gun and take some rich people with you.

Just Filter the water again and it will remove 99.9% of the remaining 0.01%

I dont think its possible. Either you are informed about the shit happening in the world and you feel despair about it. Or you are uninformed and live a happy(?) life.