One of the best preventatives for me is being retired. Until very recently, the weather around here has been nasty, so I didn't spend much time out in public. Not being around sick people has prevented me from caching the flu.
Around here, it seems the flu has peaked, but it's still very much active. As the weather improves, I will likely be out more. With my luck, I'll catch the flu in April when the epidemic is almost over.