Humidity
Test May Unmask Anthrax Spores
Faster
identification could save lives, researchers say
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February 11, 2003 > Scientists
who launched a research project on a lark may have stumbled upon a
test to quickly detect signs of possible anthrax contamination.
Spores
in the family of bacteria that includes anthrax plump up 
immediately
when they are exposed to humid air, says Buford Price, co-author of
a new study and professor of physics at the University of California
at Berkeley.
A
positive humidity test could be the "first step" in warning about
potential danger on the battlefield or in a post office, he says.
Scientists
have been busy trying to develop rapid ways to detect anthrax since
deadly spores entered the nation's mail shortly after the Sept. 11,
2001, terrorist attacks. Depending on the method used, current tests
take between one hour and 24 hours to confirm that a substance may
be anthrax, says Philip M. Tierno Jr., a germ warfare expert and director
of clinical microbiology and immunology at New York University Medical
Center. Another more accurate test can take 12 hours.
Rapid
tests for anthrax are important because "the faster it is detected,
the faster treatment of those exposed can begin," Tierno says. "There
is a high death rate for those exposed and not promptly treated."
At
UC Berkeley, Price and colleagues began to study bioterrorism after
the anthrax-by-mail attacks and decided to investigate the spores
that carry the deadly germs.
They
report their findings in a recent online edition of the Proceedings
of the National Academy of Sciences.
Spores
are essentially tiny cocoons that protect the Bacillus family of germs,
which includes anthrax, from the environment, Price says.
"The
germ only has two stages," Price says. "The cell is alive and has
to bring in nutrients and have some water around it in order to survive.
The other form is a spore. One of these cells senses danger and starts
the process of converting itself into a spore. Most biologists think
the [anthrax germ] cell totally shuts down all of its energy-burning
abilities and is completely dormant."
It
is not clear how long germs—including anthrax—can remain
in suspended animation in spores. "There are people who claim they
could be down for a million years," Price says. "The upper limit hasn't
been established."
However,
the anthrax germs in spores come back to life when they sense they
are in a safe location. Like, say, a human body, Price says.
Price
and his colleagues found they could kick-start the wake-up process
by blowing humid air over spores of the Bacillus family of germs.
When viewed through a specially designed microscope-video camera device,
the spores became slightly larger almost immediately. The device,
used in physics, allows researchers to precisely examine movement
in tiny objects.
"The
spores act like the world's fastest sponge, and no one knew that until
we made these observations," Price says.
The
humid air appears to send a signal to the cell inside the spore that
"we've got water," Price says.
The
humidity test currently allows scientists to only identify spores
in the Bacillus family of germs. The next step is to refine the process
so researchers can identify an anthrax germ, Price says.
It
may be possible to distinguish different types of spores—including
those bearing anthrax—based on how quickly they expand when
exposed to humid air, Price says.
For
now, though, the humidity test may help investigators determine whether
suspicious spores should undergo more complete testing, he says.
Tierno,
the germ warfare expert, says the findings are "promising," but more
research needs to be done to determine if the humidity test will help
investigators who are faced with suspicious substances.
Always
consult your physician for more information.
FDA
Approves Drug to Protect Against Nerve Gas
The
US Food and Drug Administration (FDA), preparing
troops for a possible war in Iraq, says it is approved a drug that
would protect them from deadly nerve gas.
The
drug, pyridostigmine bromide, is the first approved under the agency's
"animal efficacy rule." That rule states that a drug can be given
to humans when it has been shown to work in animals, and that it would
be immoral or impractical to test it in humans. The idea behind the
rule is to make drugs available in the event of bioterrorism.
Pyridostigmine
bromide would protect troops who may be exposed to nerve gas, also
known as Soman, which causes muscle failure and death from respiratory
failure, according to the FDA. It has worked in monkeys
and guinea pigs.
Soldiers
would have to take the drug every eight hours before an expected exposure
to nerve gas; the FDA says the drug will not work
after they are exposed.
The
approval is only for combat use, the FDA announced.
Always
consult your physician for more information.
Online Resources
American
Medical Association
Center
for Civilian Biodefense Strategies
Centers
for Disease Control and Prevention (CDC)
National
Institutes of Health
Proceedings
of the National Academy of Sciences
US
Food and Drug Administration (FDA)
