* Isolation, even if it were possible, may be exactly the opposite of what
is needed right now. Despite the fact that the constant transfer of bees
leads to the transfer of pests and disorders, the exchange of honey bee
stock may actually increase the vigor of the bees themselves. Quoted for
review purposes only:

> Some researchers are wondering if commercial honey bee stocks are based on
too narrow a genetic base— and that this makes them vulnerable to diseases.
Honey bee colonies comprise a large number of related animals that live at
high densities and exchange food by mouth; these are ideal conditions for
the development of epidemics. Workers have numerous defences against
disease, including an innate immune system and behaviors in which some
workers seek out disease brood and remove it from the colony. To be
effective, behavioral defences in particular require a high level of genetic
variation *within* colonies. This allows colonies to respond resiliently to
the variety of pathogenic and other challenges they face. If all workers are
the same, they may solve one problem brilliantly but be more vulnerable to
others. 

from 
What’s Killing American Honey Bees?
by Benjamin P. Oldroyd
PLoS Biology | www.plosbiology.org

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