Wasn't there another article posted a few months ago, concerning French hives having the same problem?
IIRC, it mentioned a Far East Asian bee virus, that Asian bees were acclimated to, but that was deadly to Western bees in vitro. The culprit was very closely related, genetically, to a virus Western bees are pretty much immune to.
We don't keep bees, but we do have apple blossoms & clovers, and a growing shortage of pollinators.
A co-worker told me today of these angry, evil wasps that are killing honey bees at an alarming rate...they bite the heads off of the drones then bust their way in and kill the Queen.
We are NOT amused!
I’ll see if I can get details from him, or find an article.