Influenza perspective

It should be noted that "regular" non-pandemic influenza (apparently H3N2) kills tens of thousands each year in the U.S.A. alone as a baseline. From a 2003 CDC press release:

Using new and improved statistical models, CDC scientists estimate that an average of 36,000 people (up from 20,000 in previous estimates) die from influenza-related complications each year in the United States.

Theoretically, infecting people with a relatively benign form of H5Nx might firewall a pandemic version by offering up at least partial resistance. The downside would be an increase in deaths due to the normal course in influenza. As well, one would have to ensure no other forms of influenza were present in order to avoid unintended recombination.