A lot of you have had it by now, or are having it or are about to be exposed. This year's flu is called "H3N2" and this week it's doing big business in about 47 states, Chicago and New York. If you've had a flu shot and if you wash your hands several times a day for 20 seconds, (which is the time it takes to hum "Happy Birthday to You" two times through) you might reduce your odds of getting sick.
But your biggest ally is your immune system. It's hard, during flu season, to avoid inhaling a virus or two (or three, or 10,000), but that doesn't mean they're going to take you over. You have an army of defenders in you, ready to take them on.
Here's what the battle looks like, deep down in your cells. This is the happy version — when you win.
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