Having worked in a hospital for seven years, I have been privy to medical arcanum: formulae and bits of wisdom long kept outside of traditional scientific journals. These whispered revelations occur in dark corners of cafeterias after hours, or in offices, the door closed, ears attuned to the sounds of potential lurkers.

I must admit to no longer being able to keep these extraordinary medical solutions to myself. The time has come to start spilling the beans so that more people can benefit from these miracle cures.

Medicine has long known how to prevent infections such as the common cold and influenza from being transmitted from one contaminated patient to a healthy individual. I am ready to share that knowledge with you.

No, the answer lies not with an opaque pill made from ground-up elephant tusks, nor from a proto-Indo-European incantation.

The mystical answer comes in the form of a question: do you know where your hands have been?

Imagine yourself grocery shopping this winter. You enter the store, grab a shopping trolley, and move it to the first aisle. Your nose is a bit runny from the temperature change, so you rub the mucus off. You grab a few products and put them in the trolley. Further down the aisle, you ponder whether to buy marshmallows or not while stroking your chin.

Three days later, you sneeze at work. This sneeze is but the first of a long line of sneezes. Congratulations! You caught yourself a rhinovirus. You have a cold. How did that happen?

Let’s rewind history, à la Will Graham on Hannibal. There you are touching the handle on the trolley in the supermarket. But what’s on the handle?

Let’s rewind further. A secretary with a bad cold has her hands on that same trolley, two hours before you come into contact with it. She coughs into her hand and touches the handle again. The sputum is rubbed onto the plastic: the virus takes hold and waits.

Forward two hours later, you touch the handle, then rub your nose with a finger that’s teeming with an impressionable viral population. You next carry these viral particles to your lips as you wonder whether or not to buy corn-syrup-and-gelatin confections.

I gather that most people are not particularly conscious of where their hands have been. Increasing one’s awareness of one’s manual wanderings can have a major impact on the infections one ends up with.

The influenza A virus (flu) has been reported by Flu.gov to survive on hard, non-porous surfaces for 24 to 48 hours and on porous surfaces for fewer than 8 hours¹. If the surface is wet, the virus can persist for up to three days. Studies have shown that, once the virus lands on your hand, it only stays active for fewer than five minutes. Which leaves plenty of time to rub one’s eyes, nose, or lips. Why these particular surfaces?

Our body possesses so-called mucous membranes. These are present on the ears, nose, eyelids, genitalia, and anus. While these membranes can produce mucus to prevent invaders from coming in, their anatomy makes them attractive ports of entry for viruses and bacteria. As a side note, not all viruses visiting mucosal surfaces are unwanted guests; it seems some of them may make a meal out of pathogenic bacteria and serve to protect us from infection.

This route of transmission—from the sputum of an infected individual to a common surface to your hand to your mucosa—is also used, with a slight modification, by other microorganisms. Their altered method of transmission is known by the appetite-whetting name of “fecal-oral route”. Just because you don’t see it happening doesn’t mean it ain’t happening.

In this scenario, a microorganism (such as a virus causing gastroenteritis or the infamous C. difficile bacterium) will be excreted through feces. In the process of cleaning your rear, you end up with a few viral particles or bacteria on your hand. You touch the lock on the stall door. You touch the faucet. Maybe your hand washing is not perfect. Maybe you don’t wash your hands. You touch the door handle on the way out. You shake someone’s hand. They bring their hand to their mouth. Congratulations! They are now tasting your infected feces!

I am formulating these scenarios to inspire disgust but not to foster paranoia. We are surrounded (and easily outpopulated) by microorganisms. They line our intestinal tract, and it’s a good thing too. We live in a symbiotic relationship with our skin and intestinal flora. We give them a rent-free apartment and they maintain and fix the plumbing. Not a bad deal.

But some microorganisms out there are pathogenic: they breed disease. We can avoid a good number of them by ensuring we don’t touch our face when our hands are potentially contaminated and by washing our hands before touching our face.

Most people by now know that soap-and-water is the best combination and that alcohol-based solutions only deserve the silver medal. But a potential urban myth has crawled into the memesphere a few years ago: the rumour that hand dryers carry germs and should not be used.

To verify this rumour, I headed over to snopes.com, a fantastic website dedicated to the debunking of urban legends. Indeed, the claim that hand dryers blow viruses and bacteria onto your hands and that using paper towels instead is the preferred alternative seems to be wrong, although there is some evidence which is being disputed. A study conducted by the Mayo Clinic, however, was reported as proving that any of four hand-drying methods—paper towels, cloth roller, hand dryer, and just letting them dry on their own—was as effective as the rest. Until strong evidence is put forward, there is no reason to avoid using hand dryers. For the full article (including the disturbing yet unsurprising finding that only 8% of middle and high school boys wash their hands after using the bathroom), head over here.

Good hand hygiene and awareness carry an impact beyond our personal health: they help prevent the transmission of infections from one patient to the next in a hospital. Or they would if they were part of common practice among nurses and doctors. In a critical essay entitled “System Failure versus Personal Accountability – The Case for Clean Hands”, Dr. Donald Goldmann cites hand hygiene compliance among healthcare workers as being “in the range of 40 to 50 percent”². This is how a patient enters the hospital with one condition and leaves it with a bonus infection, sometimes from a multidrug-resistant organism like MRSA or VRE. These are known as “nosocomial infections” or hospital-acquired infections.

According to a report from the Public Health Agency of Canada, cases of methicillin-resistant Staphylococcus aureus (MRSA) rose from 0.46 cases per 1000 admissions in 1995 to 5.10 in 2003 in Canadian hospitals part of a surveillance program to document nosocomial infections³. In 2009, that number had gone up to 9.47. Next time you pay a hospital a visit as a patient, make sure to tell the treating staff to wash their hands before they come into contact with you. Bonuses are nice in the form of paychecks, less so in the shape of an illness.

As temperatures descend, forcing people to spend more time in close quarters, upper respiratory tract infections, like the common cold and the flu, will rise again. If you want to avoid sniffling and coughing for weeks on end, here’s a little game to play. For the rest of the day, keep track of what your hands have touched. Stop yourself before touching your face and ask this: have my hands come into contact with a common surface? A door handle? A pole in the subway? The back of a chair in the cafeteria? An old magazine in a waiting room? Coins? Your computer keyboard and mouse which your coworker would never ever use? The refrigerator door handle touched by your significant other and your three children?

Keep your hands away from your face unless they are clean. In the high-tech world in which we live, it’s a low-tech, highly efficient solution to keeping the flu and other infections at bay.

Another way to reduce your chances of sneezing and coughing this winter? Get vaccinated. And don’t listen to Jenny McCarthy.

(Feature picture by Crossett Library)

1. Flu.gov. “Interim Guidance on Environmental Management of Pandemic Influenza Virus.” Accessed September 28, 2013. http://www.flu.gov/planning-preparedness/hospital/influenzaguidance.html#

2. Goldmann D. “System Failure versus Personal Accountability — The Case for Clean Hands”. N Engl J Med 2006; 355:121-123. Available at http://www.nejm.org/doi/full/10.1056/NEJMp068118.

3. Public Health Agency of Canada. “Surveillance for Methicillin-Resistant Staphylococcus aureus in Canadian Hospitals – A Report Update from the Canadian Nosocomial Infection Surveillance Program.” Accessed September 28, 2013. http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/05vol31/dr3103a-eng.php.