According to what I'm reading you need to take most of the reporting, an particularly those maps, with a grain of salt. Quite a few of the number listed as 'swine flu deaths' have not been confirmed as such and a considerable number are being listed simply because someone died of an unknown disease, respiratory disease or unclassified flu.

Point being that people die. That death from an unknown disease is pretty common. That tuberculosis, pneumonia and other respiratory diseases are common. That even when the focus is further narrowed to just flu there is always some background of one of the more common flu types going around. It comes down to some people simply finding out how many people have died in an area and then assuming all of them expired because of swine flu without spending much time to specify how certain the reports are.

Effects Measure has a good riff on this:
http://scienceblogs.com/effectmeasure/2009/04/swine_flu_what_did_you_expect.php

Your best defense is still to avoid crowds, avoid touching your face, frequent hand washing, and, if you think it will help to keep your hands away and/or you go out into the public, wearing a N-95 or better mask.

And, please, if your feeling sick, don't try to tough it out and go to work or continue as if nothing is wrong. Stay home.

If you do buy masks consider buying masks with an exhalation valve. They are much more comfortable for long term and hot weather use. The most durable and comfortable I have found are the Mouldex brand with the exhaust valve.