login:
fromIP: E127.0.0.1

MSNBC.com

Virus becomes new suspect in bee die-off
Genetic tests find link between colony collapse and little-known microbe By Alan Boyle
Science editor
Updated: 12:22 p.m. AKT Sept 6, 2007

Scientists have found a new prime suspect in the
deaths of about a quarter of America's honeybees,
a mystery that could take a multibillion-dollar
toll on the nation's agricultural industry.

Months of genetic testing have fingered a virus
that was first reported in Israel just three
years ago and may have passed through Australia
on its way to the United States. The correlation
between Israeli Acute Paralysis Virus and the
mysterious bee disease a known as Colony Collapse
Disorder, or CCD a was reported Thursday on the journal Science's Web site.
Although the scientists behind the research
cautioned that they haven't yet cracked the case,
their study provides enough curious coincidences
to keep even the fictional detective (and beekeeper) Sherlock Holmes buzzing.
The economic effect of the bee disappearances
goes far beyond the lost honey: In fact, the bee
industry's primary impact is felt through the
crops that the insects pollinate a products that
are valued at $14 billion to $20 billion
annually. Since Colony Collapse Disorder first
came to light last year, the malady has affected
an estimated 23 percent of the nation\s
beekeeping operations, with losses of up to 90
percent. Other countries are reporting mysterious bee losses as well.
The disorder is characterized by the rapid
disappearance of a colony's bees, even if there
are adequate stores of food in the hive. The bees
just seem to fly off into oblivion a hinting that
the malady somehow affects the insects\ navigational sense or learning ability.
For months, researchers have been struggling to
figure out the causes of CCD. Some even proposed
that cell-phone radiation was disrupting bee
colonies. Penn State entomologist Diana
Cox-Foster, the lead author of the Science
report, said the cell-phone theory was on the
bottom of the list of suspects. But she said it's
likely that several factors are contributing to
the bee disappearances a including environmental
stresses, pesticides, viruses and parasitic
Varroa mites, which all weaken the bees' immune systems.

The latest research moves Israeli Acute Paralysis
Virus to the top of the list as a "significant
marker" for Colony Collapse Disorder, the
researchers reported. And they said the technique
they used could be applied to other disease
outbreaks as well, even those that afflict humans.

The genetic game\s afoot
The scientific sleuths began their investigation
early this year by sampling bees from four
colonies that suffered a collapse, and two
healthy colonies. They also took samples from
apparently healthy bees imported from Australia
and royal jelly from China. Royal jelly is a
special food secreted by bees that is also used in cosmetics.

Those samples were run through gene-sequencing
machines and meticulously analyzed. The
researchers subtracted out the honeybee genome
itself, then identified the genetic markers of
bacteria, fungi and viruses that were left over.
A similar technique was recently used to identify
182 species of bacteria living on human skin.

Penn State's Edward Holmes concentrated on an
in-depth analysis of viruses found in the bee
samples. "This is breaking new ground in trying
to look at how viruses work in this class of
animals," he told reporters Wednesday during a pre-publication teleconference.

"We found a remarkably high viral burden in bee
populations. ... We characterize in this paper
seven different viruses that circulate in bee
populations. Only one of them was consistently
associated with CCD and royal jelly," he said.

That was Israeli Acute Paralysis Virus, or IAPV a
a little-known bug that sets bees' wings
shivering and eventually causes paralysis.
IAPV-afflicted bees are typically found dead
outside their hives. IAPV was also detected in
the Australian bees as well as two of the four Chinese royal jelly samples.
These initial clues led the researchers to look
for IAPV and other suspected pathogens in more
bee samples. They checked the genetic sequences
for bees collected over the past three years from
30 colonies that suffered a collapse and 21
healthy colonies. The presence of IAPV was found
to be the best indicator for Colony Collapse
Disorder, with a 96.1 percent correlation.


Not so elementary
"I hope no one goes away with the idea that we've
actually solved the problem," Jeff Pettis of the
U.S. Department of Agriculture's Agricultural
Research Service told reporters. "We still have a
great deal of research to do to resolve why bees
are dying in the U.S. and elsewhere."

Among the questions yet to be answered:
Is IAPV really a cause, or will it turn out that
vulnerability to the virus is merely a consequence of the disease? How and when did IAPV get into the United States?
Why did the Australian bees (and even a few
American bees) seem healthy even though they were carriers of the virus? What roles are played by other bugs that were
found in the bee samples, such as the Kashmir bee virus and Nosema fungi? If the cause or causes can be definitively
identified, what can be done to stop the collapse?

The first task ahead is to confirm the linkage
with the virus and figure out the actual
mechanism behind Colony Collapse Disorder. Not
everyone is convinced IAPV will turn out to be
the culprit. Researchers from the U.S. Army and
Montana-based Bee Alert Technology have turned up
IAPV and other viruses in sick and healthy bees a
but have not found any pattern of correlation.

"For the good of the industry, we wish they had a
smoking gun and a quick answer, but we're not
convinced they're there," Bee Alert's Jerry
Bromenshenk told msnbc.com. He said he and his
colleagues have turned up more than a dozen
suspect viruses, including "a bunch we're still scratching our heads over."
Scientists suspect that some sort of organism
will turn out to be the leading cause of the bee
collapse, whether it's IAPV, a different virus or
a combination of bugs. That's because irradiating
beehives appears to make them safe for recolonization, Pettis said.
The Australian connection is another line of
investigation: The United States allowed the
import of packaged Australian bees in 2004, and
reports of bee disappearances began soon
afterward, Pettis noted. That may be how IAPV
came into the country, though Pettis said it's
also possible the virus was here before that time.

Colin Henderson, one of Bromenshenk's colleagues
at Bee Alert, said it was still premature to
assume that the virus was passed from Australia
to America. Pettis said tests of bee samples that
were taken in the United States and frozen before
2004 could shed light on whether there's a connection or not.

If Australian bees are carrying the virus, why
aren't bee colonies collapsing Down Under? Pettis
noted that the Australian bees aren't afflicted
by Varroa mites, which have decimated America's
wild bee population in recent years. As a result,
the Australians may have weathered the stress of
IAPV better than their American cousins. "That
alone could account for the differences between the two countries," he said.
In the weeks ahead, the researchers behind the
Science study will try combining IAPV with other
stress factors to see if they can experimentally
create the conditions that tip a healthy bee colony into a collapse.
Is there a 100 percent solution?
Pettis said it's still too early to propose
putting new restrictions on bee imports. "We're
looking at the science behind it and what we feel
needs to be done, but no decisions have been made at this time," he said.
Just to be safe, beekeepers should refrain from
using imported royal jelly in their hives, he said.

Pettis said Colony Collapse Disorder was almost
certainly the result of a "combination of
things," and he didn't expect a magic antiviral
bullet to appear anytime soon. "We're really
right now going to have to rely on beekeepers to
continue just to manage nutrition, parasitic
mites, Nosema, things like that a and try to keep
bees as healthy as possible," Pettis told msnbc.com.

There's more hope on the horizon: Recent research
in Israel indicates that some bees have become
resistant to IAPV by incorporating the virus'
genetic code into their own genes. Creating
virus-resistant strains of bees, either through
genetic modification or old-fashioned breeding,
"is a very intriguing idea," Pettis said.

At the same time, the strategy used to track down
the genetic correlation between Colony Collapse
Disorder and the suspect virus provides a "road
map for rigorously and efficiently addressing
outbreaks of infectious disease," said W. Ian
Lipkin, a molecular biologist at Columbia
University's Mailman School of Public Health who
was the corresponding author for the Science study.

"I really do think that these new technologies
will revolutionize our approach to epidemiology
and the characterizing of outbreaks of infectious disease," he said.
If the strategy were available in 2003,
public-health experts might have been able to
track down the roots of severe acute respiratory
syndrome, or SARS, in much less time than the
months that were required back then, Lipkin said.

"We would be able to get similar sorts of answers
in as short as a week," he said.

In addition to Cox-Foster, Lipkin, Holmes and
Pettis, the researchers behind the Science study
included Sean Conlan, Gustavo Palacios,
Phenix-Lan Quan, Thomas Briese, Mady Hornig,
Andrew Drysdale, Jeffrey Hui and Junhui Zhai of
Columbia University; Jay Evans of the USDA-ARS
Bee Research Laboratory; Nancy Moran and Vince
Martinson of the University of Arizona; David
Geiser, Dennis vanEngelsdorp, Abby Kalkstein and
Liwang Cui of Penn State; and Stephen Hutchison,
Jan Fredrik Simons and Michael Egholm of 454 Life Sciences.

&#A9; 2007 MSNBC Interactive

URL: http://www.msnbc.msn.com/id/20612274/
MSN Privacy . Legal
&#A9; 2007 MSNBC.com