Boy or girl

[user 18806]

I see. If he was struggling, perhaps he'd been a little less on top of varroa control. You have the treatment in place so you are on top of things.
I know people who only think about treating for Varroa when they see signs of DWV!

There was a thread on here a while back that said to treat in early autumn and then in spring. Doesn't matter if you see the mites or not.
That was my plan, to use Apiguard, but then injured hand, so went with Apivar, due to temperatures dropping soon.
Reading as much as I can, and trying to do right for the bees.

Will switch to the vented? Floors next year.

 

[Erichalfbee]

Does that mean the DWV vectored by Varroa is a (are) specific strain(s) to which the bees have reduced tolerance?

Not entirely. DWV has quite a few strains. I forget how many. When they occur naturally in a bee they are at some sort of equilibrium and don’t cause disease. In varroa one strain will predominate. There is no equilibrium and that one strain predominates and causes disease. fatshark on here is the expert

Try here
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4072795/

There’s lots on internet if you google DWV variants A and B
https://www.ncbi.nlm.nih.gov/m/pubmed/31075870/