I'll throw out the following for review and comment:
 
This August, one of my hives had what I first thought was European Foulbrood
(bad brood pattern, and dead shrunken larvae in cells).   An ether roll test
got 10 Varroa mites/300 bees (~1% infection rate).   The ether roll test
results were about what I expected, as the colony had been treated with
Apistan early this spring.  The dead larvae were still white, everything was
dry, and August was a dry month.
 
One of our bee inspectors declared the problem to be the early stages of
Parasitic Mite Syndrome (PMS, and I hope somebody thinks of a better
acronym).  Apistan strips were installed, and the problem had cleaned up when
I next visited the colony 6 weeks later.
 
Everything seems to fit the descriptions of PMS that I have read, except the
low mite count on the ether roll survey.  Anybody out there have similar
experiences?
 
W. G. Miller
Gaithersburg, MD