Cord Jefferson confesses he used to not wash his hands after peeing. But "perianal sweat" changed his mind:
The perianal area is the small patch of flesh just outside the rectum, a spot on the human body that "inevitably becomes loaded with fecal bacteria," according to [assistant biology professor Pat] Fidopiastis. ("Frankly, toilet paper only satisfies your visual senses into thinking that you're clean"). When you start to perspire, even a little, sweat from the perianal area starts dripping around in your underwear, eventually getting into the fabric and moving onto your genitals.
"But what about oral sex?" I ask. "We never tell people to clean their crotches before oral sex the way we tell them to wash their hands before they eat." Fidopiastis says that's because the human mouth is actually far less hospitable to bacteria than, say, chips and dip at a party.
The Dish 