I came across this article yesterday when looking for something for my boss.
It says that the further north men live, the more faecal bacteria can be found on their hands. In Newcastle, more than half the men's hands they tested were contaminated. And these were commuters, professional people (I assume but it seems reasonable from the article) that you might expect to, maybe, wash their hands after they use the toilet.
And the weirdest thing (or maybe the most unsurprising) was that it only applied to men. Not women. There was no north-south divide with women's hand cleanliness.
It makes me want to scrub my hands after every time I shake hands with a man.
Scrubs them with bleach.