Eileen Reynolds interviews author Jennifer Ackerman, who spells out why we get sick:

Experts say that the best advice for dodging cold bugs may be the simplest: Wash your hands and don’t touch your face. If you can adhere to these two rules, you could be well on your way to cold-free dreamland. But this is easier said than done. Just try not touching your face for a day. Most of us do so one to three times every five minutes, or two hundred to six hundred times a day. (We also pick our noses about five times an hour.)

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