Hi all!
Ted Ficher wrote:" ...Apistan.  If varroa kills not directly but by acting as a
vector for virus (or
bacterial) disease, perhaps the damage was already done before the
treatment was applied......"
 
Last autum/winter several beekeepers here in Denmark suffered situations
like the situation Barry described: Well fed colonies abandon/diminishes all
of a sudden during autumn. This is thougth to be caused by a virus called
Acute Paralysis Virus (APV), bees leave hive and become paralysed out in
the field, or loose orientation (Thus possibly spreading varror by entering
another hive). If the varroa level has been to high during summer - colony
will die in autummn - the colony is stroken and removing the mites migth be
too late.
IMHO Regards Morten Petersen