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The question: If and when I get sick this winter, will covering my mouth really keep germs from spreading? Or is it just a courtesy maneuver?

The expert: Dr. Nicole M. Bouvier, Assistant Professor of Infectious Diseases at Mount Sinai Hospital's Icahn School of Medicine

The verdict: "It's not entirely clear," Bouvier said.

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"Researchers have seen that a fair number of respiratory particles still escape into the surrounding air, even when an barrier like a tissue, sleeve, hand, or surgical mask is placed in front of the cougher's mouth," she said. Plus, the droplets that sneak past cough-blocking barriers are the tiniest ones, which are light enough to hang around in the air for hours and small enough to penetrate your cube mate's respiratory tract.

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One thing you can do to prevent the sickly spread is keep all particles away from your hands—either by coughing into a tissue or lugging antibacterial spray everywhere you go. Note that in lab conditions, many viruses survive longer on hard surfaces like doorknobs and keyboards than on porous surfaces like cloth or paper.

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Whether or not you cover your mouth or become the office pariah by letting your coughs fly free, the best way to prevent germs from spreading is simply by washing your hands. Why? The average Joe touches his nose and/or mouth 3.6 times every hour and foreign objects (like those doorknobs and keyboards) 3.3 times every hour, according to a 2012 National Institutes of Health-led study (PDF). To add insult to infection-filled injury, 95 percent of people don't wash their hands correctly, if at all, and more than half of men don't use soap, per the results of a 2013 Michigan State University study (PDF). Gross.

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FYI, the right (aka effective) way to wash your hands is to lather up for 20 seconds, vigorously rubbing both sides and under fingernails before rinsing well. If you go the hand sanitizer route, apply a generous layer and allow it to dry completely.

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So in the end, coughing into the crook of your elbow is probably a good idea, unless you're wearing designer threads, that is. But for God's sake, wash your hands.