Cold and flu bugs lurk everywhere, even at innocent-seeming places like playgrounds. In fact, playgrounds are more germ-infested than public restrooms, according to a recent University of Arizona study. Why? “Restrooms tend to get disinfected and cleaned often,” says Kelly Reynolds, Ph.D., the university’s professor of public health. Playground equipment doesn’t, which means harmful germs—mostly from mucous that gets on equipment after kids wipe their noses with their hands—accumulate. Because dirt can protect these cold bugs from drying out and dying, they can survive on equipment for up to three days.

Germ defense. There’s no way you can keep up with all the germs that get spread when kids play. But eventually, you can teach your child to not touch his mouth, nose, or eyes when he’s outside so the germs he picks up can’t gain entry. While hand washing is best, if there are no facilities, bring alcohol-based hand sanitizer gel and have your child use it when you leave. For the greatest germ kill, make sure your child rubs his hands together with gel for a full 20 seconds—to the tune of Happy Birthday twice. It takes that long to dislodge stubborn germs.

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