> whether CCD combs have been checked for the presence of 
> N. ceranae spores:

> Citation?

Very little has been published on CCD with such detail. 
If you doubt my memory, I can send you the audio of the 
first "CCD Working Group" meeting, where the results 
from analysis of samples of bees, comb, and pollen
were discussed in detail by the teams that did the analysis.

>  ...but we were discussing the specific issue of whether 
>  N. ceranae spores are found on combs, rather than 
>  in adult bees.

Yes, they were found, and they still can be found.  
I'd guess that more comb is now infected than not in the US.

>Is irradiation a 'traditional' treatment for nosema? 

Yes, the standard blurb goes something like:

"Comb can be disinfected by:

a) Irradiation, 
b) Maintaining comb at 50°C (120°F) for 24h 
c) Fumigation with concentrated (80%) acetic acid 
  (150 ml per stack of five supers) for one week"

Larger operations have used irradiation for years. 
In Canada, they use E-beam, and it has been used for Nosema apis
and foulbrood for years.  In the USA, there are several Cobalt 
sources, primarily used for irradiation of fruits and veggies.

> none of this tells us whether anyone has checked for the 
> presence of N. ceranae spores on comb!

I don't know where anyone might have published anything
saying so in words of one syllable, but it certainly has
come up in conversations multiple times.

I'm sure you will agree that where bees have either form of Nosema, 
comb will be contaminated/infected, and is able to re-infect future 
generations of bees if the comb is not decontaminated.

The point I thought was "obvious" here was that while the 
irradiation of comb will kill all pathogens, Acetic acid
fumigation cannot be expected to kill all particles/spores
of a suspected but unknown virus.  Either treatment is 
well-known to kill Nosema of either type, so, in retrospect, 
the similar short-term successes of both treatments in the
MAAREC test, combined with the similar long-term failure to
keep the colonies healthy lent credence to the view that 
Nosema is a significant factor in CCD.

If packages placed on irradiated combs had fared better than
packages placed on comb fumigated with acetic acid, then
I would be unable to make this point, but the similar 
short-term success of both types of comb treatments tried 
by MAAREC versus the relative lackluster short-term 
performance of packages placed on untreated combs just 
screams "Nosema" loudly. 

Now, >>> NONE <<< of the colonies in the MAAREC experiment 
did not show a long-term positive impact over a one-year 
period, but they did claim some noticeable short-term 
advantages.  This is another thing that just screams 
"Nosema".  People are finding that their yards are getting 
reinfected, as Nosema ceranae appears to be a year-round 
issue rather than the seasonal issue that Nosema apis has been.

And before you ask - Dennis VanEnglesdorp is the one who noted 
the short-term success versus the longer term lack of success,
and he made the point in several presentations made in the
Feb/March 2008 timeframe.  I am not voicing an opinion about
the health of the colonies, I am quoting the person who 
examined the colonies to assess their health as a part of
the testing.

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