Exactly, whether punter or wg you have no real way of knowing the sexual history of the people you meet, we are more likely to catch STIs/STDs because we have more sexual partners than those outside our world but that's a risk you have to accept if your going to be involved, as a wg you have to ask yourself is that added risk worth it for the money you make and as a punter is it worth it for the pleasure you get, it's not a game for the squeamish so if the fear of catching something keeps you awake at night you probably need to find another job/hobby.
I'm really not bothered I like League One.