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Trying Not to Get Sick? Science Says You’re Probably Doing It Wrong

Cold and flu viruses transfer in very different ways than we think

Don't worry, we've got you covered. (AnnaNahabed / iStock)

It’s that time of year again: coughing, wheezy, sticky people all around you, and that dread in the pit of your stomach that you’re about to get sick. What do you do? Conventional wisdom says that to avoid spreading colds or the flu, you should wash your hands frequently—ideally using antibacterial soap—and cover your mouth when you cough. 

But it turns out that sometimes, conventional wisdom is just wrong (sorry about that, mom!). We pored through scientific studies and talked to medical experts to find that some of these oft-repeated tips don't tell the whole story—while others might actually be harmful. Here's the truth about colds and the flu. (Spoiler: You should still cover your mouth when you cough.) 

1. Talking, yelling and even breathing spread the flu.

It’s not just coughing: Merely breathing releases tiny particles that can contain flu viruses. Unfortunately, these particles are smaller than a human blood cell, meaning they're pretty difficult to avoid. A 2013 study found that these fine droplets actually contain around 8.8 times more flu viruses than the coarse droplets you can see when someone sneezes (ew).

One consequence of this proliferation of droplets? You might want to avoid people who yell a lot. A recent study on the aerosols produced during human speech, which was presented at the American Physical Society’s Division of Fluid Dynamics conference this year and is pending publication in a peer-reviewed journal, expanded this research to find that yelling produces 50 times more aerosol particles than talking in a normal voice.

Yet another reason to avoid topics like sports and politics at your next holiday gathering. 


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