I know I’m the Always Sick Chick, but something’s gotta give!

Yup, that's me ^ Sick in bed hiding my Rudolph nose. And yes, this is the first photo I've released of myself on the site.
Generally, when I say that I’m “always sick,” what I mean is that I’m chronically ill with one or more conditions – allergies, asthma, anxiety, depression, etc…
But honestly, since the end of August, we have caught every single virus that has passed through our town. We have basically been sick constantly with one thing or another.
It started with a stomach bug…and a nasty one at that. It was gross. We were all vomiting about every half hour to an hour. It was awful.
Then our oldest started school and kept catching colds the rest of us didn’t get, but he was ill enough a couple of times that he had to stay home from school.
Then we all got nasty fevers. When I say nasty, I mean approaching 103 degrees. If I had gotten any hotter, I would’ve been hallucinating.
Right after the fever, we all caught colds again…2 to be exact.
Here we are in early December, and we’re all still getting rid of these colds. It’s just damned awful.
No amount of Vitamin C was going to prevent this in my mind. Schools are germ farms, and our son brings home all of it. I wish he’d wash his hands more and keep his fingers out of his mouth. If he did those things, he’d probably stay healthier.
But, at age 6 1/2, I’m probably asking for too much.
Question: How do you keep your family healthy during cold and flu season? If you never catch the viruses that frequently go around this time of year, what’s your secret?