I've heard that wearing a mask to prevent bird/swine flu doesn't work unless you change it every so often?

I've heard that after moisture soaks through the mask from breathing, the virus can actually be transmitted through the mask; anyone know about this? Seems to me since hospitals use this method it must work. Maybe they change them every so often, not wear them all day.I've heard that wearing a mask to prevent bird/swine flu doesn't work unless you change it every so often?
The main critique of the effectiveness of face masks is that the holes in the filter are far too large to stop virus particles from getting through. But that's beside the pioint, and rather ridiculous.





You aren't trying to directly stop individual viruses from getting into you...you are just stopping people's spittle (that may carry virus) from landing right on your face, where without the mask, you are likely to either wipe it away with your hand, or else inhale it or take it into your mouth. In some cases, in crowded areas, people have been known to sneeze right onto other peoples' faces. A regrettable situation to be sure!





Once the spittle lands on the mask, the virus will die. They don't move through the mask...they have no locomotion on their own. So, you change the mask every week or so and they will provide SOME protection, if you have to be in confined crowded areas.





Again, all the mask is expected to do is to stop a virus-laden spit globule from reaching your mouth and nose. So, they do work, along with regular eyeglasses.I've heard that wearing a mask to prevent bird/swine flu doesn't work unless you change it every so often?
If that's true then they probably do change them.