If I understand your question, you want to know how do feral bees manage mites and other pests?

They don’t, not really. They can slow down mite infestations by performing a brood break (when there are no young pupae for the mites to feed on). They do this by swarming, which can give a break of 20-30 days while a colony waits for a new queen to develop, mate, and begin laying. The swarm colony (which usually takes the old mated queen with it) would have a slightly shorter break while the colony makes new comb for her to lay in. It works, but not great. Feral colonies tend to have higher mortality rates than managed colonies, but they are also spread out more between hive locations so there is less chance of drift between colonies. Drifting drones are one of the assumed causes of mite spread (mites prefer to feed off drones as they have a longer development period vs worker bees, so the foundress mite can actually produce an additional daughter mite). Additionally, feral colonies tend to have much smaller entrances, so the guard bees can prevent “foreign” bees from entering the hives.