waldig wrote:

>Is the thinking that Australian bees are not affected by the virus because
varroa mites are not in Australia yet?

Yes. From the report:

The varroa mite, for example, absent in Australia,
immunosuppresses bees, making them more susceptible to
infection by other organisms, including viruses.

Other stressors may include chemical pesticides used on
plants pollinated by bees and in hives to control pests. Crop
pesticide use is similar in both the United States and
Australia. 

Miticides are widely used in the United States but
not in Australia, and can have adverse effects on colony
health; however, miticide use did not differ between
CCD and non-CCD operations as determined by detailed case
histories.

from
"A Metagenomic Survey of Microbes in Honey Bee Colony Collapse Disorder"
Diana L. Cox-Foster, et al

www.sciencexpress.org 
6 September 2007

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