I'm starting to wonder why no amount of evidence will reverse our increasingly germophobic culture. When I was a kid - long, long ago - not everything was wrapped in plastic. Supermarkets didn't offer antimicrobial wipes to protect us from the deadly, deadly shopping carts. We weren't afraid to touch each other.
Beyond basic hygiene, there comes a point at which the germs aren't real - they're moral. Religions can become obsessed with "clean and unclean," and our secular religion is way, way down that road. It always seems to end up with certain classes of people becoming untouchable.
I knew a man once who never opened a tin can without first wiping the top with bleach. I swear I'm not making this up, Everybody was surprised when both his sons came down with asthma. Meanwhile, my son of the same age was munching dirt in his mom's garden, and today he enjoys robust good health.