It's not unusual to see someone in the course of your public outings wearing what looks to be a surgical mask. It's enough to make you wonder if you missed an important announcement.
Most face masks you see in public are due to major respiratory issues or a deficiency in the immune system that puts the wearer at great risk of viral infection even in normal situations.
If you do contract swine flu, you should wear a flu mask if you're traveling or putting yourself in close proximity to others. If you don't have swine flu and are caring for someone who does, you may want to wear a mask -- but you need to be sure to dispose of the mask immediately after leaving his or her proximity. If you wear the same mask repeatedly or touch it with your hands, you may be more likely to get yourself infected than if you hadn't worn any mask at all.
Wearing a mask is a good idea if you work in a hospital or primary care center and make contact with patients who have flu symptoms. You may also want to wear a mask if you are going to a waiting room in a hospital or public health clinic, depending on the spread of the swine flu strain in your community.
Using a face mask isn't a failsafe against catching swine flu. And, after a while, masks get uncomfortable. Your best bet overall is to wash your hands frequently and avoiding touching your eyes, mouth or nose.