>>...globalization with the massive movement of organisms (read micro-organisms) introduce unique interactions such that the "new" or unexposed host has little or no biological immunity.

Right.  Global warming is having a direct effect, too.  Many spiecies are moving northword.  Tiger mosquites, native to the Indian Ocean area, can now overwinter in parts of Italy.  They recently vectored a disease onto humans there that resembles malaria.

>>Conditions had probably been dirty before this time & rats had been around--what triggered this catastrophe?  It looks very much like a  
new introduced pathogen response to a population without immunity.

Hygiene is a key in allowing the immune sytem develop countermeasures before getting overwhelmed first.  As is nutrition (vitamin D and other nutrients).  People get colds in the winter more in the northern hemisphere than the tropics because their bodies are covered up the sun and don't produce much vitamin D.

>>...and they will certainly elucidate more of the Bee immune system along the path.

In the glorious words of T.S. Elliot:

"We shall not cease exploration.
And at the end of all our exploring...
will be to arrive where we started...
and know the place for the first time."  :))

Waldemar

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