As probiotic enthusiasts will tell you, not all microorganisms are bad. Many of them, like viruses, cause diseases that can’t be treated. Some of the worst diseases you can get come on suddenly and don’t give much hope of survival. You could be at risk for more than one of them.
Some are genetic. Many are untreatable. Thankfully, most aren’t contagious — but some can be. Here are some of the word’s worst diseases — many of which you’ve probably never heard of.