20 Tips To Prevent, Treat Colds and Flu

Keep the windows closed.

Although cracking a window next to your sneezing office neighbor might give you peace of mind — since theoretically, it would help circulate out infected air — chances are it won't do much to protect you. "Unless someone literally sticks their head out the window or moves out to the fire escape, opening the window won't have any measurable benefits once the flu virus is in the air," Dr. Adalja says. FWIW, the flu virus's outer coating hardens in cold, which helps it remain viable while passing between people, according to researchers of a 2008 study published in Nature Chemical Biology.