To elaborate just a bit, going off the top of my bald head.
Condoms are most ineffective with herpes and other viruses such as genital warts...I am not going to type the viral name cuz I can't spell it cuz i am drinking but its something with a palipimoriviurs or something like that.
This particular virus has infected some 29 trillion people. Only three of them know they have it though. Maybe my statistics are wrong, but I believe that is the most worrisome transmission disease that swingers should be aware of, even though most females show no symptoms..or because of it.