Yeah. It happens all the time, absolutely happens all the time.
Here’s one that I wrote a scene for and even did some readings from. The pitch on it was, what if viruses and bacteria evolved to give people magical talents when you caught the disease. This idea that a bacteria doesn’t actually want to kill you, or a virus doesn’t want to kill you. It wants you to live and spread it. You getting sick is a side effect. What if the side effect is, you got the common cold, all the sniffles and everything, but you could fly as long as you had the common cold? What would that do to society? What happens when someone invents penicillin and can wipe out half of these magical talents? What happens if people start catching a disease that makes everything they touch start on fire?
So it was a story about basically fantasy Jack Bauer, who’s a member of the fantasy CDC, who tries to stop diseases and the problems thay cause. But in order to do his job, he has to keep his immune system terrible, like this weakling who can barely get up the steps, so that he can quickly catch diseases to get the powers he needs to with the outbreaks of these things. It’s just a really cool concept that I’ve never been able to gel into an actual story. It hasn’t worked every time I’ve tried to write it.