“Just to be clear, men & women engage in that risky form of sexual activity also.”
It’s the anal sex part that spreads it. And where it is probably true that it occurs sometimes between a man and a woman, it would almost always be initiated by a bi male.
If a hetero man go out and sticks his organ in a pile of dog doo before banging the “old lady” you would get the same results.
No sympathy there for him either... (or for her if she is aware if his perversions)
They may be swingers. They may not even be married, and have agreed to see others when they so desire.
It could be a lot of things, not just bi-sexual men. One or both could be intravenous drug users. Could be the woman is the sole drug user, and the husband/boyfriend gets infected from her. Perhaps the woman is the one who is engaging in sex with other males, with her male main partner unaware of her activity. There are even more scenarios I am not even mentioning, but I think you get the idea.
The Bible says: the sins of the father will be visited upon the children. In other words, actions of parents most likely will result in negative consequences for their children.
Again, it is tragic when anyone, child or adult, who gets hurt because someone whom they trust has deceived them.