Ted wrote: Are you saying comb can become contaminated with virus? I had
thought viruses needed a host to live(if
viruses really are alive).

Judy Chen showed that viruses do indeed contaminate the comb.  Queens also
carry viruses, so all the bees have some degree of exposure.  The key point
is whether the viruses are inactive (latent) or active (apparent).  Bee
colonies generally don't have much problem with viruses unless there is an
added vector.  Varroa fits the bill for the vector.  Once the varroa
infestation gets high enough, the vectoring allows the virus to go epidemic.
See my article in Feb ABJ for reference.
Randy Oliver

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