Number of germs in our normal daily lives. Certainly surprised me a bit.
Doorknobs are dirty but on the "low side," and people should not be very worried about touching too much doorknobs and catching a cold or flu because of it. Computer keyboards and telephones, on the other hand, are brimming with bacteria, and have more bacterial load than an elevator button, the handles and button on the communal microwave oven, or the office water fountain. The average desk harbors 400 times more bacteria than the average toilet seat! Where there are bacteria, there can be viruses, which are known to hang onto a clean and dry surface for days (!!) and to a wet surface for weeks (!!!) On Public Toilets: bathroom sinks have high bacterial counts, and the dirtiest handles are urinal flush handles. Think diarrhea instead of any sexually transmitted infections (STIs) --- the most common toilet germs found are Norwalk-like viruses or caliciviruses, shigella, and salmonella --- which can all cause diarrhea. "Clean laundry" is really dirty laundry. Professor Gerba says, "There is about a 10th of a gram of feces in the average pair of underwear, and you don't want to be doing your handkerchiefs with your underwear.." Uh-oh! Make it a habit to wash your hands well not only before eating but AFTER eating, and also AFTER doing the laundry. Accountants, bankers, teachers and doctors are the professions most highly exposed to bacteria and viruses. Surprisingly, lawyers have the least exposure.
This facts were revealed from a study done by a professor Charles Gerba, a microbiologist and clean water expert at the University of Arizona.
The summary I got it from here.