I saw someone interviewed recently on TV talking about using hydrogen peroxide in one's nose when they are flying to kill any flu bacteria. I just did a google search on it, check it out, there are many links for fighting flu using hydrogen peroxide. Some say put it in your ears others say apply it to a tissue or q-tip and rub it into your nostrils, that would certainly be something I would do. After all, as we all know, it kills bacteria. If you can carry a small amount of it on the plane with you, you can apply it while on a flight or when you reach your lay over.