from LAT article
"Australian bees do not suffer from CCD, leading researchers to speculate that the virus acts
synergistically with chemicals in the environment or with another infectious agent, such as the
varroa mite, which is not common in Australia.
Experiments are underway to determine which combination of virus and chemical or infectious
agent, if any, causes the disease, and researchers hope to have an answer this year. Researchers
are also examining archived bee specimens to determine whether the virus was present before
2004.
"Our results indicate that [the virus] is a significant marker for CCD," said Dr. W. Ian Lipkin of
Columbia University's Mailman School of Public Health, a coauthor of the report published online
today by the journal Science. "The next step is to ascertain whether [the virus], alone or in concert
with other factors, can induce CCD in healthy bees." "
and
"All of the bees, both healthy and sick, had a set of eight distinctive bacteria "that have not been
found in any other environment or host," said coauthor Nancy A. Moran of the University of
Arizona. "They are all unnamed species about which we know very little. They probably perform
essential functions in bees, providing essential nutrients or contributing defenses against
pathogens."
Similarly, there was "a remarkably high viral burden in bee populations, both those with CCD and
those without it," said coauthor Edward C. Holmes of Penn State University. "There were seven
different viruses, but only one was consistently found with CCD."
Israeli acute paralysis virus was found in all the CCD specimens, but in neither of the healthy
specimens. It was also present in some bees imported from Australia and in two of four samples
of royal jelly imported from China. The imported jelly is normally used as a cosmetic, but some
beekeepers feed it to larvae to produce queens.All of the infected colonies, moreover, had bees
from Australia or were housed close to bees from that country. U.S. officials are considering
reinstating the ban on bees from Australia, Pettis said, but it may be too late to limit the damage
already done.
Israeli acute paralysis virus was discovered in 2002 in dead bees from Israeli colonies by virologist
Ilan Sela of the University of Jerusalem. In experiments reported this summer, Sela found that
injecting the virus into bees killed 98% of recipients within days.
The symptoms in the Israeli bees -- shivering wings, paralysis and death -- are different from
those exhibited by American bees. But Holmes speculated that the virus might have undergone
slight genetic changes that had altered its pathogenicity.
"We know from other viruses that very small genetic changes can turn a benign virus into a very
virulent one," he said.
Or it may be that the symptoms are different in bees whose immune systems are stressed by the
varroa mite or by being trucked from farm to farm during the growing season."
Bob this does not sound like a *weak* hypothesis. As usual science does not offer a black and
white answer but rather a strong signal of where to go next to build the case. Geez why should we
be surprised that the varroa mite could play a role in transmitting this virus and explain why no
IAPV in Australia.
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