From: Mike Lorrey (mlorrey@datamann.com)
Date: Mon Oct 22 2001 - 11:41:22 MDT
This might be of use to someone or some company;
http://www.economist.com/science/displayStory.cfm?Story_ID=821937
Testing times
Oct 18th 2001
>From The Economist print edition
Instant screening for anthrax is now possible
THE difficulty of isolating, growing and distributing suitably lethal
strains of anthrax means that serious biological attacks have, so far,
been mercifully few and far between. This is, however, of little comfort
to the large numbers of people opening letters or parcels containing a
mysterious powdery substance that turns out to be something innocent, or
a hoax.
Unfortunately, the two established methods for identifying anthrax and
other microbial contaminants involve time-consuming laboratory
techniques.
One is to try to culture an organism from the powder, and then subject
it to a barrage of chemical tests to identify it.
The other is to amplify and identify its DNA.
The first takes days, and the second is a sophisticated technique that
few laboratories are yet able to manage. So, even if the result is
negative, chaos may already have been caused and the act of terrorism
rewarded.
A better solution would be to screen on the spot. And technology to do
this is now available. It uses a test strip, costing $20, that looks
like a pregnancy-detection kit.
The Guardian Bio-Threat Alert System is a joint development by Alexeter
Technologies, based in Wheeling, Illinois, and Tetracore, of
Gaithersburg, Maryland. It takes 15 minutes to react to the presence of
anthrax, and it is the only rapid field test now available.
Tom Fryzel, the marketing manager of Alexeter Technologies, says that in
the past fortnight the company has shipped what would normally be three
months' inventory to emergency services, corporate-security outfits,
groups connected with the armed forces and a few places that you can
probably imagine but we cannot talk about.
The test is done by shaking up a sample of the suspect material in a
proprietary solution, and then placing drops of the mixture on to the
strip.
Antibodies specific to anthrax are present on the strip and attach
themselves to any anthrax bacteria in the sample. When this happens, the
antibodies detach themselves from the strip and migrate along it, to
reveal two red stripes printed underneath.
For forensic purposes, each strip also carries a chip that stores its
manufacturing details. When a strip has been used, it is placed in a
unit which writes the results, along with the date, time and name of the
operator, into the chip. These data can then be made available to any
criminal investigation or legal case that results.
The founders of Tetracore were part of a team of scientists from the
Naval Medical Research Institute, in Bethesda, Maryland. They are now
working on new methods for detecting a range of infectious agents such
as plague and smallpox, using field versions of gene-amplification
technology.
A particularly promising line for the company is a genetic field test
for foot-and-mouth disease, which it hopes will be brought out in Brazil
this week. The test works in an hour, and can detect the virus even
before symptoms have appeared.
Anthrax-detection strips seem likely to become a common feature in the
postrooms of large organisations. They will not, however, give absolute
assurance. A negative response still has to be checked in the
laboratory. But it provides enough certainty to avoid panic.
And a strong positive, according to Mr Fryzel, means that you might as
well close the doors and round people up there and then.
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