Many sources of information on the varroa life cycle are surprisingly vague about this, but it seems that varroa do not perist in egg form outside a living colony. In other words, for them to carry on year over year in the same colony, it has to have live bees/brood in it to sustain some adult varroa. Therefore, if the colony dies entirely, all the adult varroa presumably die...my concern was that re-used comb might contain varroa eggs that could infect other bees. Not possible? Of course there may be varroa-transmitted viruses and a whole constellation of other stuff on those combs, some desirable , some not. But as far as varroa is concerned, there should be no carry-over from dead-out equipment??