Find out where germs hide in our homes and offices

People try to avoid germs by washing their hands and applying sanitizer, but a recent study shows that this common practice prevents only a small fraction of spreading bacteria.

University of Arizona Microbiologist Dr. Charles Gerba has been finding germs that make us sick in places that are much less obvious than at gas pumps and bowls of nuts in a bar.

Dr. Gerba found that about one-third of women's purses are infected with fecal matter.

Many women put their purses on the floor in bathrooms then place them on surfaces around utensils and food.

"They just picked up everything on the restroom floor and moved it to their kitchen countertop where they're going to make a meal," said Dr. Gerba.

Women's accessories are not the only items that can spread bacteria.  Men's wallets are dirty culprits as well.

"You're sitting on it all day, very close to body temperature which a lot of bacteria like to grow at," said Gerba.

If a man does not wash his hands as often as he should, his wallet is even dirtier than the average man's wallet, says Tucsonan John Shotts.

When comparing men and women, who has the germiest desk?

Dr. Gerba says that women tend to have germier desks than men because they tend to eat at their desks more often.

"The average desk in an office has about 200 times more bacteria than a toilet seat because people clean toilet seats, but apparently they don't clean their desk," said Gerba.

Dr. Gerba's team put a virus that cannot infect people on one person's hand to see how bad it really is when an employee goes into work sick.  They sent that person into an office from the front door and went all around the workplace.

"We found, within four hours, one person could contaminate 50 percent of the surfaces and the viruses showed up on 50 percent of the other people's hands," said Gerba.

Many offices, malls, and restaurants use refillable soap dispensers that ironically do the exact opposite of cleaning your hands.

You can get up to 10 million bacteria just in a few drops of liquid soap coming out of refillable dispensers that never get cleaned out, says Gerba.

"You're putting more fecal bacteria on your hands than was in the toilet after you flushed it," Gerba said.

The same problem could arise at home if people keep refilling old dispensers.

But if you do not yet have the "heebie-jeebies," there is still one more place where Gerba found the ickiest germs.

Gerba says candy bowls almost always get fecal bacteria in them over time. This is due to the same reason nut bowls at bars are so germ-infested.  It's bad enough that people put their unwashed hands in the bowl, but when they're indecisive about which candy they want, they sort through the bowl and touch all the candies to find that perfect one.

If you use reusable grocery bags, and never wash them, Dr. Gerba has a message for you.

He tested a few and found some pretty disgusting germs, including fecal bacteria.

"How they get germy is you put meat products in here and they leak. They get liquids in here and the bacteria will grow in these. And in our interviews only three percent of the people we talked to ever admitted they ever washed one of these reusable bags," Gerba said.

And leave the bags in a warm place, like your car, and Dr. Gerba says it's like the germs are in an incubator.

Gerba recommends using the cotton bags that you can throw in the washer every time you use them.

He says some of the other bags have to be hand-washed or they fall apart, and he doesn't think very many people will want to hand-wash the bags every time they use them.

Speaking of groceries, many of us love the convenience of self-checkout.

Gerba's crew decided to check out the self-checkout touchscreens.

What they found could take your appetite away.

"We found not only fecal bacteria on a lot of them, we also found MRSA which cause skin infections and C. difficile (Clostridium difficile) which causes diarrhea," Gerba said.

Many grocery stores provide disinfectant wipes so we can clean the grocery cart.

You might consider using one on your hands after you touch the self-checkout screen.

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