Re: Drone comb loaded with mites
If 25% of drone larvae have a mite in them, at that level it is likely that 6% of worker brood will have mites in them.
But you have to sample around 100 drone cells because the mites can "cluster" in one small area of comb and give a wrong reading in a small sample.
The 25% drone brood infestation is considered a critical level for the hive, the level at which many textbooks recommend the hive is treated. For you though, it is a simple matter to remove the drone brood thereby removing a good portion of the mites. As above, the comb can be discarded, or frozen then returned to the hive.
Just to complicate things , there is a body of thought in the treatment free community, that mite levels should be left to run their course in the hope that maybe the hive will throw off the mites. However if this is your only hive & you want to play safe you would treat it or at the very least remove drone brood and continue to monitor.
44 years, been commercial, outfits up to 4000 hives, now 120 hives and 200 nucs as a hobby, selling bees. T (mostly).