> N. ceranae infections have been described to be different from N. apis
symptoms. A gradual depopulation of adult bees, higher autumn / winter
colony mortality, and finally the queen surrounded by only young bees have
been observed in southern Europe,

Here is the OIE description of N apis infection: "Any inherent natural
defence by a bee colony against a heavy infection with the parasite depends
on the colony size as well as on the prevailing weather conditions during
the early part of the autumn of the previous year. If
these conditions are unfavourable, the overall life expectancy of the
colony is reduced. This may lead to the
premature death of bees during winter or early spring. In a typical case of
a colony being depleted because of a
Nosema [apis] infection, the queen can be observed surrounded by a few
bees, confusedly attending to brood that is
already sealed... During winter, Nosema apis infected colonies may become
severely depleted of bees or die out altogether. The majority of Nosema
apis infected colonies will appear normal, with no obvious signs of disease
even when the disease is sufficient to cause
significant losses in honey production and pollination efficiency"

So I'm not seeing that the signs of infection by either parasite are
greatly different.


 >whereas such severe symptoms or effects have not been described from more
temperate climates nor from South or North America.

I have described such symptoms and effects from N ceranae, and have plenty
of photos of colonies in the process of suddenly depopulation when the N
ceranae infection moves into the majority of the bee.

> The described field symptoms differ between the parasites, as do the
> seasonal prevalence.


My research and personal experience do not support the above statement.


> >Fecal deposition within bee hives is associated with N. apis infections,
> but this is not the case with N. ceranae.
>

The above statement is also not supported by research.  N apis does not
depend upon dysentery to effect fecal transmission.  Since older bees do
not consume pollen, their feces are not noticeable.  And all the old school
N apis researchers made clear that dysentery could certainly spread N apis,
but was not due to infection.  Recent research by the Solter lab has
confirmed the oral-fecal transmission route of N ceranae.

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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