Here's a link to the actual papers (and code): (Note that none mentions "spam")

http://mscompbio.codeplex.com/wikipage?title=PhyloD

Overall it's pretty kickass, and the papers themselves tell why it's HIV in particular: HIV evolves extremely quickly within a specific host, so any general solution needs to be able to account for a virus that can adapt to your specific treatment regimen.

And that's the link to spam-fighting: rapidly changing strategies to fool your immune system into thinking it's a good cell that should be let in, which is amenable to similar spam-fighting approaches.