Treatment thresholds may be possible when considering spore levels rather
than incidence of disease.  Europe, Australia and New Zealand that sample
honey and adult bees for AFB spores, and based on the results, figure out
how heavy the risk of having AFB in the operation.  AFB spores can be
detected in honey at levels below which symptoms are seen, making it
possible to provide a better idea of when antibiotics are no longer
necessary for protection.   Acknowledging that not all beekeepers use
antibiotics, a threshold based on spore levels could also direct beekeepers
to adjust the intensity of comb decontamination (by irradiation or
replacement) or colony inspection efforts.

Are there any beekeepers on BEE-L from countries with an active honey
spore-detection service?  How do you use the service?

> But to see AFB in a hive and say, it's under control by the bees, is
> utter nonsense. It ain't under control and it ain't going  away on
> its own. I have kept bees for almost 30 years and I have *never* seen
> a hive get rid of AFB on its own.

I agree with Peter, however, there is evidence that not all colonies with
clinical symptoms of AFB necessarily die:

Woodrow, A. W. and H. J. States.  1943.  Removal of diseased brood in
colonies infected with AFB.   ABJ 83: 22-23.

The caveat was:
"In the three years no colony in which more than 100 cells of (AFB) diseased
brood were found recovered from the disease".

Let us be clear, the results of the study clearly do not suggest that
colonies with fewer than 100 cells with AFB should be left unmanaged to see
if they clean themselves up.  The point is that AFB is not like Varroa and
the disease does not, in all cases, become immediately worse; some colonie
will recover and some will recover only temporarily.

A few researchers believe AFB may be present in colonies at levels below
which visual inspection can detect.  One scenario for how this may be
happening is that although larvae keep getting infected, nurse bees keep
yanking out diseased lavae, making it hard to spot a low level infection.
For this reason, I would agree with Peter that a management threshold may
not be easily linked to the incidence of visual symptoms may not be very
useful; it is too late.  Maybe there is hope, however, for reducing
antibiotic use following a threshold tied to the levels of spores in an
operation / apiary / colony.

Adony