I imagine that by the time varroa levels reach the point that they are
being noticed that they've been around for quite a lot longer, or put
more simply, by the time you start noticing them they're already firmly
established.  This is of course unless beekeepers have been doing
regular tests in order to detect the very first varroa mite to don a
kilt.
 
I agree with David Green that the only impact a detect and burn policy
will have will be on the beekeepers and varroa will continue unabated.
A better strategy would be to sound the alarm and make a concerted,
coordinated effort to treat for mite infestation.
 
Ultimately the solution to this scourge will be through breeding, either
breeding a better bee or a lesser mite.  A strain of less prolific mites
has been discovered (Harbo) and there are hopes for some strains of bees
being more resistent.  However, until the breeders are successful the
practical keepers of bees must do and learn as much as they can about the
enemy in order to keep their livelihood going.
 
Whether destroyed by varroa or destroyed in a futile effort to slow
varroa's advance, a practical beekeeper's livelihood is negatively
impacted equally.
 
Aaron Morris - thinking dead bees are dead bees regardless why.