Masks work to protect people against swine flu, a Harvard internist reports, as long as there is a tight seal about the mouth and nose. In this article, Dr. Gurley gives a list of ways to protect yourself from the swine flu, including information on mask use. She reports that expert panels and pandemic review boards, in general, do not recommend masks despite saying they work, both because masks often aren’t properly fitted, and because masks in public are not “widely accepted.” But...