HI Everyone,
Peter makes a point that varroa stress will lead to greater problems
with AFB.  There is another issue here with varroa namely the impact on
the brood from the mites.  You can get symptoms very similar to AFB in
colonies that don't have AFB infection.  It looks like AFB at first look
but not quite right if you are experenced with AFB diagnosis.  One
result is colonies being thought to have AFB when they actually don't.
Of course this could impact the insurance situation you have with hive
destruction for control as Peter points out.  How long can you go on
with more colonies impacted than you have in the past?  Are all field
AFB finds confirmed in the lab before hive destruction?  What are the
varroa levels in the infected outfit?  When the symptoms are due to
varroa treatment of the mites results in healthy brood very quickly
without any other treatment or hive destruction.

A point from this side of the pond.  When colonies are destroyed for
disease control only a few states have any kind of reembursement in
place.  In most cases the cost is to the beekeeper which of course makes
a major difference in how beekeepers view such disease control
activities.  Most will destroy visabily infected combs and treat with
antibiotic because it is considerably less expensive in the long run
than waiting until more colonies show the infection and burning them.

FWIW

blane


******************************************
Blane White
MN Dept of Agriculture
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