system
Given the following post, respond as if you're commenting on Reddit:
human
Why does it spread germs/illnesses to leave a bathroom with hands unwashed, yet oral-genital contact is not regarded as a surefire way to get the same illnesses?
gpt
Washing your hands after using the bathroom is not just about the germs gathered during the time using the bathroom. Ingraining that habit into people while they are at a sink with water gets them to clean away other germs they may have picked up without having to make a special trip to wash. 

Human fecal matter is the real germ problem, not the human genitals. The genitals themselves, if clean should carry no more germs than the rest of the skin. Ineffective wiping however leaves fecal matter, and potentially it ends up on the hands. Washing removes it. In reality a male standing to pee, or either gender who doesn't wipe at all shouldn't be gaining any more germs on their hands than from any other activity. Its just easier to train people to always wash after a bathroom event so the bases are covered. It has the added benefit of removing other germs gathered before the bathroom event.