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作者：非文人 在 罕见奇谈 发贴, 来自 http://www.hjclub.org
INFECTIOUS DISEASES:
Deferring Competition, Global Net Closes In on SARSMartin Enserink and Gretchen
Vogel
Four weeks after the sudden appearance of severe acute respiratory syndrome
(SARS), researchers still aren't completely sure what causes the potentially
fatal disease that has sickened thousands around the world. But they have
scored at least one victory: From the chaos of the widening epidemic has
emerged a globe-spanning team effort dedicated to finding the culprit as
fast as possible.
With a little help from modern communication technology, the World Health
Organization (WHO) has set up a global network of labs that has largely
survived the fierce rivalries traditionally dominating the competitive field
of virology. "I would say this is historic," notes James Hughes, director
of the U.S. National Center for Infectious Diseases in Atlanta. By pooling
resources and intellect, "we're marching two or three times faster," adds
virologist Ab Osterhaus of Erasmus University in Rotterdam, the Netherlands.
This week, members of the network published an article in The Lancet and
submitted four papers to The New England Journal of Medicine (NEJM) to document
their work. Most scientists now agree that a new coronavirus is the most
likely cause of SARS, which had caused 2671 cases in 19 countries by Tuesday,
including 103 fatalities. But some believe the virus may have an accomplice,
such as the recently discovered human metapneumovirus that Frank Plummer
and colleagues at the National Microbiology Laboratory in Winnipeg isolated
from several SARS patients.
Growing concern. Children in Hong Kong don masks to shield against viral
infection. By Tuesday, nearly 1000 cases had been reported in the city.
CREDIT: ANAT GIVON/AP
The heart of the worldwide scientific onslaught on SARS is the office of
German-born virologist Klaus Sthr on the fourth floor of the communicable
diseases building at WHO headquarters in Geneva. Sthr has no lab of his
own at WHO, but shortly after SARS was detected, he decided to try to weld
together research groups into "a global virtual laboratory." Even he was
skeptical that it would work. During past outbreaks, labs often fought fiercely
to be the first to finger a culprit, and sharing data or samples was often
out of the question. "Scientists by nature are very competitive," Sthr says.
But all 11 labs he invited to participate accepted, and since 17 March,
Sthr has chaired daily teleconferences during which researchers share their
findings. His standard greeting--"good morning, good day, good evening"--has
come to symbolize the network's global reach. Genetic sequences, photos,
and other data are posted on a secure Web site, and reagents are shipped
around the world within hours of a collaborator's request.
The first hints about the probable culprit came on 21 March, just 4 days
after the initial teleconference. Late that evening, Malik Peiris of the
University of Hong Kong e-mailed group members that he had isolated a virus
from patient tissues. It grew more slowly when exposed to blood serum from
patients recovering from a SARS infection, he said, suggesting they had developed
antibodies to the virus. Serum from healthy controls had no effect on the
virus. An initial electron microscope image suggested a coronavirus, Peiris
reported.
Soon the findings were replicated in other labs, and on 24 March, Julie
Gerberding, director of the U.S. Centers for Disease Control and Prevention
(CDC) in Atlanta, announced the finding to the world. Scientists have detected
the virus or antibodies that target it in many infected patients but not
in more than 800 healthy controls, Sthr says.
To obtain more definitive evidence, Osterhaus has infected monkeys with
the virus to see if they develop a SARS-like disease. As Science went to
press, a similar study was awaiting approval at the U.S. Army Medical Research
Institute of Infectious Diseases (USAMRIID) in Fort Detrick, Maryland.
Coalition. A team in Beijing is the 12th group to join the unprecedented
"global virtual laboratory" tracking the SARS epidemic.
Still, some suspect a role for human metapneumovirus, which has been isolated
from SARS patients in some parts of the world--including Canada and Hong
Kong--but not others. Last month, an independent group from the University
of Liverpool, U.K., published a study showing that this virus appears to
exacerbate symptoms in infants infected with respiratory syncitial virus.
The Canadian researchers suspect it may do the same in SARS patients. "I'm
convinced that they are right, that there are metapneumoviruses in their
patient samples" that may be playing a role in the disease, says Christian
Drosten, a virologist at the Bernhard Nocht Institute for Tropical Medicine
in Hamburg.
But attention is focusing on the coronavirus. A subset of the group is working
to develop a test sensitive enough to detect infections early in the course
of the disease, says Sthr. Meanwhile, USAMRIID is testing thousands of antiviral
compounds against the virus in cell culture and plans to slog through all
drugs currently approved for any condition by the Food and Drug Administration,
says Army virologist Peter Jahrling. If an approved drug works against SARS,
it could be available much faster than a new one. CDC and other labs are
comparing the virus's genome sequence to those of other coronaviruses--which
can infect a range of avian and mammalian species--to determine its likely
origin.
For network scientists, Sthr has tried to orchestrate the fair distribution
of a key commodity: scientific credit. He initially proposed that they submit
three papers to NEJM: one produced by three groups in Hong Kong, one co-authored
by German researchers and CDC, and one by groups that found the metapneumovirus.
That plan fell apart when CDC, which had been invited by NEJM to write
a paper, decided it preferred to go it alone. Fortunately, NEJM editors said
they would consider publishing all four. Drosten has teamed with colleagues
across Germany as well as Osterhaus and a group from the Pasteur Institute
in Paris to describe the methods they used to track the coronavirus. "It
appears there's enough flesh on the bones for everybody," says Osterhaus.
Meanwhile, Sthr is also compiling a paper for The Lancet chronicling the
current collaboration. He concedes to being slightly taken aback last week
when, after each lab had submitted 250 words about its own role, Gerberding
stole some of the network's thunder in an NEJM editorial that was posted
online 2 April. But his hope is that the example set by the SARS network
will long outlast any debate over who came first.
作者：非文人 在 罕见奇谈 发贴, 来自 http://www.hjclub.org |
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Science (4/11/03)上有关SARS的文章
