I have a Friend who is a Biologist, one of the Guys I have Coffee and BS with every morning, and he was explaining the whole Virus/Vacination thing to us one morning, and it's pretty interesting...
A couple of weeks ago on a Sunday I came home from a ride and my Wife was so sick with the flu, I'm talking couldn't even stand up, so I took her to the ER at Hoag..
When we arrived there the waiting room was packed, there were three other Ladies there with Flu-like symptoms and they put the four of them on "Fastrack" to get them in isolated Rooms..of course it's not possible to distinguish Swine Flu from any other kind of flu without testing the Blood/Urine and it turned out she had a combination of Allergies, Asthma and a Flu Virus, not swine Flu...
The following Day my Friend told me there were 200 People admitted with Flu at Kaiser, one tested Positive for Swine Flu...
I'm not a Doctor, but it seems that if anyone has Flu symptoms go to the local ER and go through their procedure, at least if it turns out to be swine flu they will document it which will help in collecting valuable data and probably isoloate you from the general population so you will be doing others a favour too...
Apparently the "Great Flu" of 1918 started in the spring, subsided during the Summer of that year then came back later with a vengeance and killed millions of People...
Oh, back to the OP, Flu Masks...we have boxes of them at work available free to employees, the Boxes become empty pretty rapidly but I've never seen anyone wear one at work....my Company <em>makes</em> all the Flu Masks everyone is wearing, although not at my Division...so keep wearing them!! You're helping our stock values.