Top 10 Places Cold and Flu Germs Hide

Reading time: 7 – 11 minutes

Cold and flu germs hide everywhere and while most of us love surprises, suddenly coming down with the cold or flu isn’t one of them. Keeping your hands clean goes a long way towards preventing illness. In addition to that, here’s some tips on the places where cold and flu germs hide and the precautions you can take to stay healthy.

Handshakes, sneezes and kissing

It happens to everyone: you cover your mouth when you sneeze, forget to wash your hands and then later greet someone and shake their hand. Cold and flu viruses spread one of two ways, primarily by air or through direct contact. Handshaking can be one of the main culprits in direct contact cold and flu transmission.

When a person sneezes, small particles are expelled from the nose at over 100 mph and can cover a three-foot radius. When you have the flu, the virus makes itself at home in the lining of your nose and causes irritation, swelling and sneezing. Sneezing when you you’re sick can easily transmit germs to those around you, so remember to cover your mouth when you sneeze and wash your hands afterwards.

Let’s face the facts. Kissing exchanges saliva, and if you have the cold or flu, you’ve just passed it on to the one you love. Do them a favor, if you’re sick, don’t smooch.

Kitchen sink sponges and dishcloths

Bathrooms are commonly associated with germs. However, the kitchen actually harbors more bacteria than any other room in the home [1]. Sponges and dishcloths are notorious for harboring bacteria [2-3]. Why? Because they can sit wet for days with bits of food on them. A sponge or washcloth that’s wet with food and kitchen-counter germs makes an ideal breeding-ground for bacteria that can cause food-borne illnesses. Then, when you wipe down the kitchen countertop, those germs – the same ones that cause a cold or flu to run rampant through a household – have just been spread all over the kitchen. Your best bet? Ditch the sponges in favor of dishcloths you can wash every few days.

Restrooms and toilet seats

Public restrooms can be dirty. On top of all the dirt and grime, people with cold- and flu-contaminated hands touch handles, locks and toilet paper rolls. Add to that fecal bacteria and public restrooms are a nasty place. After using the restroom, be sure to wash your hands properly.

Toilet seats are places where fecal bacteria hide. Bathroom floors and countertops also harbor germs. Indeed, it’s been shown that bacteria and viruses from droplets produced by flushing a toilet remain airborne long enough to settle on surfaces throughout the bathroom [4-5]. Significant quantities of microbes float around the bathroom for at least two hours after each flush. Here’s a tip: close the toilet lid when you flush.


Doorknobs are a prime suspect in the transmission of the cold and flu. Germs have been shown to survive on doorknobs and other inanimate surfaces for more than two hours [6-7]. In order to minimize exposure to germs, latches can be taped open where possible or doors can be kept open to reduce the need to touch doorknobs. You can also pull your sleeve over your hand or use a tissue when touching doorknobs.

Drinking fountains

A 2005 study by NSF International, an independent, not-for-profit organization, found as many as 2.7 million bacterial cells per square inch on drinking water fountain spigots [8]. Spigots that stay wet, particularly on a leaking fountain, can harbor bacteria. This is especially true if someone has coughed, sneezed or spit on it recently. Avoid drinking fountains that don’t look clean and run the water for 15 seconds prior to use to help wash away contamination.

Shopping carts

Have you noticed that most grocery stores now offer antiseptic wipes when you grab a grocery cart? There’s a reason for that – children put their mouths on shopping cart handles, leaving behind mucus and saliva. That means you can pickup a lot more than a great deal on bananas when you go grocery shopping. Another tip: don’t place unwrapped fruits and vegetables in the grocery cart seat. Diaper-aged children sit in them and accidents do happen.

Elevator buttons and escalator handrails

Elevator buttons and escalator handrails are dirty and can be a prime place to catch a cold. Try to avoid touching them if you can. Here’s a tip for elevator buttons: use your elbow or knuckle instead of fingertip to press the button. Or take the stairs – the exercise will do you good. Researchers have found that about 30 minutes of exercise three to four times per week may help decrease your risk of several types of cancer.

Office workspaces

The average office workspace is dirtier than many places listed in this article. People talk, sneeze, eat and breath all over their phones, keyboards and desks everyday. Disinfect your workspace, particularly if you share your desk, computer or phone with other employees.

Gas station pump handles and keypads

One word — yucky. In addition to all the grease and grime, gas station pump handles and keypads are touched by many people everyday, making it a breeding ground for bacteria. Here’s a great idea: keep a small bottle of alcohol-based hand antiseptic in the car to use after you gas up.

Airplanes, subways and buses

Have you been on an airplane recently? If they make the seats any smaller, you’ll be sitting on someone’s lap. If a person is sick on a plane, the people in front, behind and to either side of them are at risk for getting sick. About 50% of the air is recirculated and is passed through special air filters to remove dust, vapor, bacteria and mold. Viruses are too small to be trapped by the filter, but viruses are typically attached to droplets, which are filtered. However, there are still ways that infections can be transmitted to passengers. Body-to-body contact is one mode of transmission. Another mode of transmission is from large droplets that are sprayed when a person sneezes, coughs or talks. The virus or bacteria sprayed at you infects your body through your eyes, nose and/or mouth. Still another mode of transmission occurs when larger infected droplets partially evaporate and becomes widely dispersed in the air. It’s simple: don’t fly when you’re sick. If you’re on an airplane and someone nearby is sick, ask if you can move to another seat.

Okay, any public transportation is bound to have germs lurking in them. Subway and bus poles and handles are no exception. To protect yourself, wear gloves when touching the poles and/or handles. If you do touch the them without gloves, don’t touch your eyes, nose or mouth until you’ve washed your hands. Another idea is to sit so you don’t have to hold anything.


  1. Rusin et al. Reduction of faecal coliform, coliform and heterotrophic plate count bacteria in the household kitchen and bathroom by disinfection with hypochlorite cleaners. J Appl Microbiol. 1998 Nov;85(5):819-28.
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  2. Scott et al. An investigation of microbial contamination in the home. J Hyg (Lond). 1982 Oct;89(2):279-93.
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  3. Scott and Bloomfield. The survival and transfer of microbial contamination via cloths, hands and utensils. J Appl Bacteriol. 1990 Mar;68(3):271-8.
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  4. Gerba et al. Microbiological hazards of household toilets: droplet production and the fate of residual organisms. Appl Microbiol. 1975 Aug;30(2):229-37.
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  5. Barker and Jones. The potential spread of infection caused by aerosol contamination of surfaces after flushing a domestic toilet. J Appl Microbiol. 2005;99(2):339-47.
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  6. Bardell D. Survival of herpes simplex virus type 1 on some frequently touched objects in the home and public buildings. Microbios. 1990;63(256-257):145-50.
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  7. Ansari et al. Rotavirus survival on human hands and transfer of infectious virus to animate and nonporous inanimate surfaces. J Clin Microbiol. 1988 Aug;26(8):1513-8.
    View abstract
  8. Millions of Germs and Bacteria Await Kids at School. NSF International. Sept 2005.
About the Author

Walter Jessen, Ph.D. is a Data Scientist, Digital Biologist, and Knowledge Engineer. His primary focus is to build and support expert systems, including AI (artificial intelligence) and user-generated platforms, and to identify and develop methods to capture, organize, integrate, and make accessible company knowledge. His research interests include disease biology modeling and biomarker identification. He is also a Principal at Highlight Health Media, which publishes Highlight HEALTH, and lead writer at Highlight HEALTH.