If I remember no EFB is tolerated. Not even one infected cell. The colony is destroyed. All the other colonies in the apiary are shook swarmed into a package box for three days then shaken onto new foundation and fed.
I’m sure Murray will be along soon to elucidate
That's at season end...ALL clinical cases are removed and destroyed at, or very close to, time of diagnosis. Even suspect colonies are taken out and culled as we do not want to wait for lab results and then have to do a long round trip after any positives are confirmed..so diagnosed AND suspected all go. Actually culled a significant number (maybe 30 orm40?) that were sampled as suspect by the inspectorate in the field but subsequently the results came back as negative (not negative to to alveii which happens a few times and are undoubtedly positives) so culled significantly more than we needed to. Contact colonies *only* are shook swarmed but after the season going into autumn or winter.
Its still all a bit experimental and I would not recommend anyone copying us at this stage. We have a broad back if the experiment all goes pear shaped...folk with a lot fewer colonies would be exposed to heavy losses if our system's efficacy varies from season to season. It is our first 'geared up' experiment this winter..so far looks good. However it is important to remember these ARE contact colonies, not clinicals...which the NBU recommended practice is actually intended for. We are bein far more severe.
Progress of the colonies currently under this regime will be reported on Twitter as normal. Units with multiple cases and thus with reason to believe that sub clinical is well established and we would be likely playing ''whack a mole' over a protracted period are now culled in their entirety, the equipment sterilized, and refilled from scratch with the product of the nucleus unit.
We are on a declining pattern, our incidence is way down on previous, and the severity is also well down, but suspect that,, as this is an EFB area now, we will meet the disease sporadically (at least) for the rest of my life. Worth remembering before folk say we are a 'dirty unit' that we DO have 4500 colonies and 1200 nucs. The national background rate in NBU figures based on the number found during inspections is 1.5% or thereabouts. That would give us in excess of 80 cases a year. Did not have that.
Yes we have EFB in our unit, but the rate is not huge and on its way down, but due to just the sheer artifact of numbers the likelihood of reaching zero is pretty slim. Defeatist or realist? Not sure yet.....but pouring hundreds of thousands into cull, replace, sterilize, and renew. Each year.