Scot McPherson wrote 'AFB ... has little effect in the honey.'
One should read that statement with caution.  It's true that a vegetative case of AFB in thre hive is far different than a sporealative case of AFB in the honey.  However, ABF spores in honey is still the number one way that ABF is spread.  The honey in a hive with a vegetative case of AFB contains literally millions upon millions of AFB spores.  Robbing honey from an AFB infectived hive brings AFB spores back to uninfected hives.  It takes very few spores (5? - I don't recall) to infect a larva less than 1.5 days after hatching.
 
So the original warning about AFB honey stands.  Unless one knows that honey does not contain AFB spores (and truthfully one cannot know for sure unless tested) then unknown honey should never, ever be fed to bees.  As far as the original question, "Will microwaves kill ABF spores?", I do not know but I would suspect not immediately or similarly to how Cobalt-60 irradiation does.  Surely microwaves will heat honey to a sufficient temperature to kill AFB spores, but such temperatures will likely render the honey useless for consumption either by humans or bees.  I'm not sure what was the intent of the original question, but when I read it my initial reaction was, "Don't go there, you're asking for trouble."  AFB spores in honey is only a threat to bees, it's not a concern for humans.  If the concern is to remove the threat to bees, I doubt (but do not kown) microwaves suffice.  Irradiation will kill AFB spores.  Imported honey in some countries is routinely irradiated, in fact MUST BE irradiated to be imported.  I imagine if microwave worked, importation laws would be different.
 
Aaron Morris - I think, therefore I bee!

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