The recent occurrences in Hong Kong are really interesting, in which you have a limited number of people who have been exposed to truly avian influenza virus. That is, all the gene segments that have been analyzed so far, to my knowledge, really look avian like. This is not a recombinant human avian virus.
So it really looks like the first time in a natural setting that humans have been infected with an avian influenza virus. It looks, however, like there is no evidence of person-to-person spread of the virus. So somehow you have an avian influenza virus that has been able to gain a foothold and replicate to at least some extent in human beings, but that the virus is not well adapted to life in humans and consequently can't really spread from human to human. But since influenza viruses mutate so rapidly, that possibility certainly exists. And if this virus was able to be passed from person to person, the risk of it becoming a pandemic virus will be very great because it's a very different virus than any other viruses that have circulated in humans in this last century. So it would be the same situation like 1918. No one would have immunity to this kind of virus and it really would spread all over the world.