Date: December 1, 1998
Abstract: For Americans, who feel snug and secure behind the shield of unparalleled military power, the thought of biological warfare raises a frightful specter. Its effects are devastating, it is indiscriminate, it is easily concealed.
But help may be coming.
A new technology designed to quickly spot biological terrorist attacks has been developed by researchers at the Los Alamos National Laboratories in New Mexico. The technique, which zeroes in on the protein toxin that causes cholera, may also be used in hospitals to detect the chemical signature of cholera well before an outbreak hits.
"For cholera [detection], it is just as good as the best lab-based method but a lot faster, much simpler," said project leader Basil Swanson.
He said the technique is also better than DNA sequencing -- a traditional method for identifying cholera -- since it can be used to isolate the organism that produces the toxin rather than simply identifying the toxin itself.
At the moment, the Los Alamos technique is limited to cholera detection, but there are plans to adapt it for identifying other dangerous biological agents as well.
"Each protein toxin is a different story in its own right," Swanson said. "The technique is flexible, but we still need to develop the appropriate recognition molecules to do each one."
Proteins, however, are not the only toxins that could be used in biological weapons.
"There are other ways that organisms can actually act to cause damage, so this would not be a panacea for detecting every possible biological agent," said Leland Rickman, medical director of the epidemiology unit at the University of California San Diego Medical Center.
Los Alamos technique generates a signal when a cholera toxin is
present. Special molecules latch onto the cholera which, when struck
with a pulse of laser light, become fluorescent.
The detection aspect of the technology is small enough to be portable, but the tool that measures the fluorescent response -- a flow cytometer -- isn't.
"Flow cytometry is a lab-based instrument and not a small fieldable sensor," Swanson said. "[But] flow cytometry has been adapted to the Biological Integrated Detection Systems that the Army uses for detection of biological-agent release in military situations."
BIDS, a mobile lab housed in a Humvee, is the best equipment currently available for detection, using immunoassay-based approaches to isolate the agent. Although BIDS is too cumbersome for immediate response, researchers hope it will soon be portable enough to carry their new technology.
It's important that some method of portability be devised. Until researchers prove the technique can work outside the lab, it remains on the shelf alongside other methodologies that are unavailable for field use, Rickman said."It's an innovative study and actually quite elegant," he said, "so it looks like a promising technique. However, it doesn't appear to have been validated in the field and there's a long way from the lab to the field" (Wired, 1998).