The mites are back in the one tray of eggs and teensy baby worms that were too small to sift out and rinse. By the way, the larger worms withstood rinsing under warm water very well, and the pupae, also. After their bath, they were placed into microwaved bedding. (People all think I'm nuts when I tell them I wash my chickens. What will they say when they hear I wash my worms?)
But I couldn't microwave the bedding in which the eggs and baby worms were. I tried letting the bedding air out for several hours, thinking it might help desicate some of the mites, but it didn't help.
So I still have the question: is there anything one can do to get rid of mites without killing off worm eggs and babies?