With the swine flu outbreak, the good news is that, at the moment, we are not dealing with a 1918 style pandemic. The current H1N1 strain -- "H1" and "N1" indicate certain proteins on the virus -- was first detected in March. A repeat of the 1918 Avian virus (or other pandemics in 1957-58 and 1968-69) would already be killing people in significant numbers in places as scattered as Singapore, Buenos Aires and Moscow. According to the Centers for Disease Control (CDC) what we are facing is simply a new strain of the common flu that is somewhat more virulent. All evidence thus far indicates that a simple paper mask is effective at limiting transmission (make sure to replace them frequently), and that common antiviral medications such as Tamiflu and Relenza work well against the new strain.
Already we are seeing disruptions to operations in the U.S. as well as other areas, particularly Mexico. For example, New York City has experienced the greatest number of swine flu cases to date in the U.S. The city has stepped up its efforts to prepare for an expanded event. The city of Mexico City is on the verge of shutting down all operations.
Various national health authorities globally were concerned about a possible H5N1 outbreak in 2007. Many of the procedures that were put into place to deal with a potential H5N1 catastrophe (information dissemination, vaccine dissemination, antiviral stockpiles, etc.) remain applicable for combating this new H1N1 strain.
As you probably know, once you have the flu, you develop a natural resistance to not just that specific strain, but any strain that is somewhat similar. H1 has been present in the U.S. for years and H1 strains regularly make it into American flu vaccines. Since it is believed that the H1 portion of this new virus is the one that's changed, in theory this will provide Americans with some limited protection.