I'm not sure, but I think the medics' masks are more to prevent transport in the other direction, such as someone accidentally spraying spittle over a compound fracture.
When I was in north China, a lot of people wore cotton masks. The air was pretty dirty, and it was bitterly cold. One doctor told me not to wear a mask, as it would increase the chance of me getting sick. Wearing a mask caused a lot of warm condensation in the cloth covering the face, which I think may be a good breeding ground for whatever is in the air, or already in your mouth/nose.
I have noticed that the medical masks tend to be more open to ventilation around the sides, so probably don't cause as much condensation, and are easier to talk through. They are also some plastic backed material (paper?), so different from the cotton I experienced. I guess they may also have antiseptic agents imbedded in the material.
That was interesting to know about the immune response to colds though. I had often wondered why people vary so much in their responses. Some of my Asian friends get a strong response for 24-48 hours, and then are fine. I usually will be crappy for 1-2 weeks, which I think helps to get futher infections.
Anyway, hope everyone feels better soon. Personaly, after spending a year or so in China, I don't get nearly so sick any more. It's a real kick for the immune system.
