Full sealed Saint Gobain with supplied air and gas mask. Nothing else will stop what is essentially just the flu. Fair warning, the effective temperatures inside one of those is about a hundred and ten, and the manufacturer recommends against wearing one for more than an hour at a time.

Also it's what Amogus is based on so you're not only sweating yourself to death, you also look ridiculous. Oh and it takes two other people to help you get in and out of one.