| Biological Warfare |
By Linda D. Kozaryn WASHINGTON -- You can't see, smell or taste them, so how do you fight biological agents?
Still, many people don't understand the nature of biological agents, how they would be deployed or how to protect themselves, according to Col. John V. Wade, an Army medical department officer who has specialized in the chemical/biological warfare field for the past 16 years. During Desert Storm, Wade served as Army Gen. Norman Schwarzkopf's medical chemical/biological warfare advisor. On Oct. 1, 1998, he became deputy for counter proliferation and chemical and biological defense to the director of defense research and engineering and the undersecretary of defense for acquisition and technology. Biological warfare encompasses "a mixed bag of bacterial agents, viruses and toxins," Wade explained. Lumping all biological warfare agents together as a class is almost as dangerous as comparing biological and chemical agents directly, they can be very different, he said. Depending on the situation, some are contagious, others are not.
Usually, we think of biological agents as an aerosol threat, according to the Pentagon expert. "Think of that as taking a liquid in an atomizer and putting it out in very, very small micro droplets. Aerosols behave a lot like chemical vapors. There's a lot of water vapor in a room, but we can't see it, or feel it, or taste it, or touch it. That's really what we'd have in a biological event." These deadly 'bugs' do have some natural enemies, Wade said. "Most biological agents don't weather well. There are lots of things that make it difficult for these biological agents to exist. You put them out in ultraviolet light and they die. They don't like drying out. The same environmental factors that keep us from having one cold after another, will help us out to some extent in the case of a biological attack." Biological agents can be dispersed one of two ways, Wade explained, either by what's known as a "line source" or a "point source."
A more commonly envisioned scenario involves a point source, Wade said. This is where the enemy launches a missile or other munitions which, upon detonation, spews biological agent directly on you -- the target. "Either way, what the enemy is trying to do is take the organism or the toxin and disperse it into the atmosphere so that the target troops then inhale it," he said. "That's really the threat of most of these agents. Just like the common cold, we get them via inhalation. "Because the agents are very small particles they can make it through our nasal passages -- evading all of the normal protective measures we have to filter things out -- and get down to the deep lung area where they then cause disease." Unlike a chemical agent attack which would cause an almost immediate reaction, a biological attack would not cause a reaction until after an incubation period. "Generally it takes 24, 36, 48 hours before our troops would start showing what oftentimes are non-descript, flu-like symptoms which then progress to whatever symptoms the specific agent would normally cause," Wade said. So, how do you defend yourself against an attack you don't even know has happened?
When vaccines are not available as a biological countermeasure, Wade said the answer is "rapid detection, warning, reporting, and masking." He said it was important to note that the protective mask is "effective against every known biological agent, including those for which we don't yet have vaccines." Defense officials are developing and fielding smaller, lighter, and simpler biological detectors, Wade said. "We have a number of systems that can now be deployed on the battlefield." The Biological Integrated Detection System, known as 'BIDS,' is a mobile lab suite that can detect four different agents simultaneously. It's mounted on the back of a heavy HUMVEE and manned by four individuals. The Army deploys BIDS companies as corps or theater level assets to do bio-detection for all forces. BIDS are point detectors, Wade noted. "You have to wait for the cloud to come to the BIDS system. We have the same type of system aboard ships called the Interim Biological Agent Detector or IBAD." After detecting what appears to be an unnatural agent, the systems first provide a warning, then determine specifically what the biological agent is.
Biological agents are considered "strategic weapons," Wade noted. "They're not a good tactical weapon. So if someone is going to use them, we want our detection arrayed out in front of, or dispersed throughout, troop locations to give us early warning." Defense officials also have developed (acquired) a long-range biological detector, Wade said. It's a laser-scanning instrument mounted on a Blackhawk helicopter that can look out about 50 kilometers. "It can't identify specific agents, but it's looking for that telltale, cigar-shaped plume that comes from someone laying down a line source," he said. "If we can see it 50 kilometers off, that gives us a tremendous amount of time either to prepare for it coming our way, or to go out and sample that cloud," Wade continued. "In the future, we'll have detectors that are light enough and small enough to go on an unmanned drone vehicle that will fly through the cloud, find out what it is, and report back."
"The beauty of this device is that it's a network sensor," Wade said. Depending on the geography, as many as 18 sensors may be arrayed around a port or an airfield. The sensors talk to one another, so you're not relying on just one of them sounding an alarm. Using an array system, the false positive rate very quickly gets down to zero, Wade noted. In Bahrain, U.S. forces have run more than 3,000 tests during 'round-the-clock' monitoring by the Portal Shield deployed there. The false positive rate was less than one half of one percent, he said. Defense officials are also developing more user- and environment-friendly decontaminates. "We're working on improved technologies which are easier on us, as well as sensitive equipment such as electronics, while still being effective in eliminating the agents," Wade said. "The equipment and materials we have for decontamination right now are pretty sturdy," he continued. "Super tropical bleach is almost as hazardous in terms of being a caustic to human skin as some of the biological agents themselves are. You sure want to have your gloves and all your protective equipment on if you're involved in using it.
But, if you can't move because you're stationed at a port or airport, Wade said, defense officials need to know what key areas need to be decontaminated. "We're doing studies to see if you take a plane up to 30,000 feet and fly it at 600 to 700 knots, is there anything left to decontaminate," he said. "Does the flight line have to be decontaminated? What happens when a hazardous material oozes into concrete? We're doing studies now to answer the questions, 'How clean is clean?' and 'What has to be cleaned for us to be able to continue our mission.' Biological and Chemical Weapons
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