Story highlights Anywhere people gather is filled with bacteria and viruses

Filthiest place in the restroom is actually the sink, experts say

Each key on an ATM contains, on average, 1,200 germs, a study found

Before trying the latest gizmo, quickly wipe it down with a disinfecting wipe

During the craziness of the holidays, the last thing you want is to get sidelined with a cold, flu, stomach bug -- or worse. But while you're checking items off your shopping list, you may be exposing yourself to germs -- like flu viruses, E. coli, and staph -- that can make you sick.

"Anywhere people gather is filled with bacteria and viruses, and a crowded shopping mall is a perfect example," says Philip Tierno, Ph.D., director of clinical microbiology and immunology at New York University Langone Medical Center.

With that in mind, we asked a panel of experts to rank the worst germ hot spots at your local shopping center. Check out the ewww-inducing results -- and tips for keeping yourself in the clear.

1. Restroom sinks

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The filthiest area in a restroom (and therefore in the whole mall) isn't the toilet handle or the doorknob -- it's the sink, our experts say. Bacteria, including E. coli, fester on the faucet and handles because people touch those surfaces right after using the toilet, explains panelist Charles Gerba, Ph.D., a professor of environmental microbiology at the University of Arizona.

"The sink area is a moist environment, so bacteria can survive longer there," he adds.

Watch out for soap dispensers, too -- not only are they handled by many dirty hands, but the soap itself may harbor germs. When Gerba's team tested liquid soap from refillable dispensers in public bathrooms, they found that one in four contained unsafe levels of bacteria.

Protect yourself: Wash your hands thoroughly after using a public loo: Lather with soap for at least 20 seconds, then rinse well. Use a paper towel to turn off the water and open the door. If there's no soap or paper towels, kill germs with an alcohol-based hand sanitizer, using at least a tablespoon of product.

Gerba also advises avoiding refillable soap dispensers (usually made of clear plastic with a removable lid) and only using liquid soap that comes in a sealed refill; if that's not an option or you're not sure, follow up with hand sanitizer.

2. Food court tables

Even if you see the table being wiped down, that doesn't mean it's clean, says panelist Elaine Larson, Ph.D., a professor of epidemiology at the Mailman School of Public Health at Columbia University: "The rags themselves can actually spread harmful bacteria such as E. coli if they are not changed and washed regularly."

Protect yourself: Consider stashing a pack of hard-surface disinfecting wipes in your purse so you can swipe the table before you sit down. "Look for ones that contain alcohol or another disinfecting agent in order to make sure you're killing germs, not just wiping away grime," Tierno says.

3. Escalator handrails

"In our testing, we have found food, E. coli, urine, mucus, feces, and blood on escalator handrails," says Gerba. "And where there is mucus, you may also find cold and flu viruses." Tierno concurs: "We've found respiratory flora on handrails," he says, "which makes sense because people cough into their hands, then touch the rails."

Protect yourself: Play it safe: Avoid touching handrails altogether, recommends Gerba, unless you absolutely have to -- in which case, give yourself a generous squirt of hand sanitizer afterward.

4. ATM keypads

After testing 38 ATMs in downtown Taipei, Chinese researchers found that each key contained an average of 1,200 germs, including illness-inducing microbes like E. coli and cold and flu viruses, Tierno says. The worst key of all? The "enter" button, because everyone has to touch it, Gerba points out.

Protect yourself: "Knuckle" ATM buttons -- you'll avoid getting germs on your fingertips, which are more likely to find their way to your nose and mouth than your knuckles. And be sure to wash your hands or use sanitizer afterward.

5. Toy stores

Toy stores can actually be germier than play areas, carousels, and other kid-friendly zones, Tierno says, simply because of the way little ones behave there. "Kids lick toys, roll them on their heads, and rub them on their faces, and all that leaves a plethora of germs on the toys," he says. The goods their parents don't buy end up back on the shelves, where your kid finds them.

Protect yourself: If you make a purchase, wipe down any toy that isn't in a sealed box or package with soap and water, alcohol, or vinegar (which has antimicrobial properties) before giving it to your child. And, of course, reach for the hand sanitizer after you've been hands-on in the toy aisle.

6. Fitting rooms

You won't pick up much from the hooks or the chair. The germ culprit? What you try on.

"After people try on clothing, skin cells and perspiration can accumulate on the inside," says Tierno. "Both can serve as food for bacterial growth." You can even pick up antibiotic-resistant bacteria, such as MRSA (methicillin-resistant Staphylococcus aureus), just by trying on clothes, says Tierno.

Protect yourself: Always wear full-coverage underwear (no thongs!) when trying on clothes, especially pants, bathing suits, and any other garment that touches your genitals or rectum. Bandage cuts or scrapes before trying on clothes, as "open wounds can be a gateway to dangerous bacteria," Tierno says. And be sure to wash new clothes before you wear them.

7. Gadget shops

While you're playing around on that new smartphone, you could be picking up germs from the thousand people who tested it out before you. "Most stores do clean their equipment," says Tierno, "but they certainly don't clean after each use."

A study published last year in the Journal of Applied Microbiology found that viruses easily transfer between glass surfaces (think iPad or smartphone faces) and fingertips. And a recent report found that of four iPads swabbed in two Apple stores located in New York City, one contained Staphylococcus aureus, the most common cause of staph infections, while another registered a bacteria associated with skin rash. That's not even counting the cold and flu germs that might be lurking.

Protect yourself: Before you try out the latest gizmo, quickly wipe it down with a disinfecting wipe. And (yes, once again) use a hand sanitizer after you're done.

8. Makeup samples

Heading to the makeup counter? You might end up picking up a staph infection right along with the latest lipstick shade. A 2005 study found that between 67% and 100% of makeup-counter testers were contaminated with bacteria, including staph, strep, and E. coli. "This study shows us that someone was sick or went to the bathroom, didn't wash their hands, and then stuck their finger in the sample," Tierno says.

Protect yourself: "Avoid using public makeup samples to apply cosmetics to your lips, eyes, or face," says Tierno, who suggests asking for a single-use unit (you open it, try it, and throw it away). If that's not available, use a tissue to wipe off the sample and then apply the product to the back of your hand.

The best line of defense: Buy then try. Returning stuff to the store may be a little more of a hassle, but it's a heck of a lot better than bringing home a nasty bug.