Reply #58: To early to attribute this one to "antigenic shift"

[Jim Pivonka]

This is in no way similar to changes in flu viruses that result from "antigenic shift" as that has been described in the literature I've seen.

This is a straightup recombinant virus. Whether any of the four components of the recombinant will show antigenic shift is not known - I am sure that will be studied carefully.

But the key idea here is that this is recombinant. Recombinant viruses are not that unusual; the difficulty with the "it happened naturally" idea here is that we have 4 (FOUR) recombinant components, not two. And none of the components has been seen, so far as is so far known, been seen in combination with any of the other components.

So we have at a minimum three novel recombinations if viruses, one avian, one human, and two swine, suddenly appearing in a new virus, and suddenly spreading very rapidly. No precursors. No animal infections known. None of the four ever seen in combination with any of he other three before.

Sorry - we cannot say that this "looks" natural, or that it reflects "antigenic shift". It just aint so.