Let's say you decide 5 cells of AFB or less, is treatable.

I run mostly hygienic bees.  I burn AFB cases.  Unfortunately, got a bit of
AFB spread due to a truck wreck containing a diseased colony.
I did an experiment last year.
Found about a dozen colonies in early spring exhibiting only two or three
cells of active AFB.  Put them in another yard with no treatment to see if
they'd clean it up on their own with a nice pollen flow.
Only about two of them did--the disease progressed in the rest.  Waste of my
time--did shake & bake, and hot-dipped the woodware.

I have really good luck shaking two or three AFB colonies out together into
a deep of foundation and feeding TM for the first brood cycle.  Requeen at
first chance to kill the AFB susceptible queen.  They act like a swarm, and
are often ready for a second box of foundation in week or so.  Have done
this for years, and rarely see any AFB in any.

Randy Oliver
Calif

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