A nice idea that dates back decades. But ...
Hasn’t the CDC advised male Ebola survivors to use a rubber for several months after being “cured”? Seems that Ebola can survive in semen for months after being killed ( don’t any better term) in the survivor.
What makes blood different?
It’s probably some kind of “shedding” issue. Maybe it’s one of the areas that tends to get pent up so takes longer for the shedding.
Whereas, everyone goes potty every day and quite frequently so sheds right from the primary disease routes quickly (and they get from and give directly to the bloodstream), the men aren’t necessarily eliminating that semen every day.
I don’t know, I’m just guessing.