I'm gonna go out on a limb here.
Gotta do it, as out on limbs is where the ripe fruit hangs.

What we have been calling "Nosema ceranae" may or may not be
actual Nosema ceranae.  What we have been calling "Nosema apis"
may not be Nosema apis, either.  One or both of what we are seeing
may be a variant of "Nosema bombi" that jumped hosts from Bumblebee 
to Honey bee.

Why do I speculate so "wildly"?  There's a number of reasons:

1) We know exactly how Nosema bombi got to our shores - it came
   here on bumblebees imported for greenhouse pollination.
   This exotic invasive pathogen has driven at least two
   species of US native bumblebees to extinction. See:
   http://entomology.ucdavis.edu/news/robbinthorp.html

2) No one seems to have a good story as to how Nosema
   ceranae got to our shores, got established, and spread.
   
3) Light microscopy (normal microscope) methods for 
   discrimination between Nosema apis and Nosema ceranae 
   been mistaken for many years by multiple highly competent
   people, and yet no one has yet compared all three types
   of Nosema (apis, ceranae, bombi) under the same
   microscope on the same afternoon.

4) Even the assumed-to-be more accurate molecular methods 
   of differing between Nosema apis and Nosema ceranae 
   (based upon RNA - the "16S ribosomal subunit sequence") 
   may or may not be able to differ between Nosema apis and
   ceranea AND bombi.  A conclusion is being made upon only
   a few hundred bases out of hundreds of millions of bases 
   in the complete sequence.  While these bases were chosen
   to differ between Nosema apis and what we are calling 
   "Nosema ceranae", there is no assurance that either type
    of Nosema is being uniquely identified using this method.
   "Screening" is never the same as making a firm identification. 

5) Eric Mussen of UC Davis confirms that Nosema apis and Nosema 
   bombi are "very close genetically", while Nosema ceranae is 
   much more closely related to other types of Nosema, such as 
   Nosema vespula.

6) No one involved in the CCD work has gotten into the taxonomy 
   issues, so there is no consensus on HOW to differ between
   any of the pathogens at hand, hence the confusion.  The 
   confusion is the same, regardless of the pathogens at
   issue, be they Nosema, viruses, or fungii.  What is needed
   in all cases is some full sequencing, anything less just
   won't do. 

7) We've had Nosema apis for years and years, but not at "epidemic"
   levels.  Since we've started to see the new nosema, the one we
   are called "ceranae", we've also seen a much more widespread
   prevalence of BOTH types of Nosema, and so has Canada.   How
   the heck did THAT happen?  Why does everyone suddenly have so
   much Nosema of both types, when in years past, Nosema apis was 
   one of the ignored problems of beekeeping, and not as universally 
   widespread.

Just to recap, this is not the first time that the data at hand
did not match the conventional thinking about CCD, yet the data
did not change the thinking as quickly as one might hope it would.

A year ago, I speculated that Colony Collapse Disorder "just had to be" 
"a pathogen problem" rather than a pesticide problem or a management
issue.

Why?  'Cause the problem clearly spread like a pathogen.  Any pesticide
problem
would have left some bees with "only the shakes" because they would only
get
a "whiff" of the poison, rather than a dose that would do lasting harm.
Any
management issue would have revealed itself in beekeeper surveys.

Last summer and fall, I stated that the actual best "marker" for CCD was
both 
kinds of Nosema (apis and ceranae) in the same hives at the same time,
rather 
than Ian Lipkin's pet virus.

The consensus and focus of attention has moved from pesticides, to 
"fungal infections", to Israeli Acute Paralysis Virus, to (at last) 
the suitably more complex mix of both kinds of Nosema, Deformed Wing 
Virus, and (after what I am sure was lots of arm-twisting to save face) 
IAPV, even though IAPV isn't correlating to CCD cases well at all.
Here's the AIA statement on the newest consensus:
http://home.ezezine.com/1636/1636-2008.04.25.11.04.archive.html


We are left wondering why such a wide range of different levels of
virulence 
has been reported for "Nosema ceranae", everything from "kills hives
dead in 
3 days" from Europe to "no worse than Nosema apis, but not as seasonal"?


The easy answer is that we are not talking about a single pathogen, or
even 
minor variants of the same pathogen.  The easy and obvious answer is
that we 
are talking about different pathogens, but we haven't bothered to figure
out 
which one is what one or what one is who.

So, I'm betting on a taxonomical surprise in the Nosema area.
This matters because we have to "know our enemy" to be able to defeat
it.

I could be completely wrong in the above.  Recall that people laughed at

Columbus, they laughed at Fulton, and they laughed at the Wright
Brothers. 
But they also laughed at Bozo the Clown. :)

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