Juanse Barros referenced:
  http://www.apitrack.com/pdf/Espania_Enviromental_Microbiology_09_2008.pdf

...The more foragers infected, the smaller the number of brood combs and 
the fewer frames full of bees
(Pearson, P = 0.001, CATPCA, Fig. S1).
This relationship did not hold for the proportion of infected interior 
bees or the spore counts. The dynamics of bees and brood combs
were related to the proportion of infected foragers and the maximum mean 
temperatures (regression stepwise: adjusted R2: 0.702). No statistical 
differences could be established with other meteorological parameters.


Taking the above in isolation!
Does this mean that a poor summer etc. as suggested by several sources 
as a root cause to colony deaths does not hold water?

Losses in Canada have so far been a result of weather induced stress.
OR:

Temperatures have influenced the # of infected foragers, which in turn 
have "failed", which then stressed population dynamics within the 
colony. This eventually resulting in an inability to maintain proper 
timing of brood production. Cumulating in collapse of the colony.

A little explanation would be welcome.
Many thanks,

Peter

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