It can't hurt and it might help. A recent study in The Journal of Infectious Diseases found that wearing a surgical mask and using an alcohol-based hand sanitizer helped reduce the number of influenza-like illnesses in a group of students living in a college dormitory. Another group of college students in the study used face masks alone, which also helped prevent influenza — but not as much as the combination of face masks and hand hygiene.
People who live in community housing — such as college dorms, nursing homes or military barracks — are at higher risk of influenza infection because they're in contact with more potentially infected people.
Flu viruses travel through the air in droplets when someone with the infection coughs, sneezes or talks. You can inhale the droplets directly, or you can pick up the germs from an object — such as a telephone or computer keyboard — and then transfer them to your eyes, nose or mouth.
Flu masks may help block airborne germs, and they may also forestall the transmission of germs from your hands to your mouth or nose. However, the best way to prevent influenza is to receive the flu vaccine, either via an injection or nasal spray.