Not sick just not enough bees in each hive going into winter. Both were new hives last year that never really built up.
david, post some pictures of the brood if there was any and the piles of dead bees if you can. i'm with edward, i'd be worried about what was wrong. i had a hive come through that was only covering 3 frames when it clustered.
Excellent advise from 10framer and edward;
We should use our dead outs as a learning experience. I always try to find the queen in dead outs as it is the usual cause. Lack of ventilation is another common one and remedies can be tweaked. Looking and performing simple tests on any remaining larva. Lack of stores or 'failure to build up' can also be 'remembered' for the following season, and 'new' remedies implemented.
While not fun, dead outs provide us with much information and experience.
Yeah, freeze those frames if the room is available, other wise 'protect' them in a cool spot by blocking 'all' entries.