Biological Weapon Detection Equipment Bioterrorism

Biological Weapon Detection Equipment

Bioterrorism is potentially one of the deadlier forms of terrorism because it can be silently introduced amidst large populations to cause untold health problems or large numbers of fatalities as well as create a world-wide panic. The key to effectively managing and coordinating a biological incident will be early detection and timely response. This includes immediate responsiveness to suspicious disease symptoms. By assimilating into an already established public health system, emergency managers would be able to respond to any local epidemiological event; protecting residents from all possible disease threats.

BIOLOGICAL WEAPON DETECTION EQUIPMENT

INTRODUCTION work published by Frost and Sullivan (2004) entitled: "Chemical Detection vs. Biological Detection Strategies" states: "Chemical and biological detection equipment is a cornerstone of the homeland security market. The need for both types of technology will continue to grow exponentially over the coming decades. Frost & Sullivan's annual report, World Chemical and Biological Agent Detector Markets, states worldwide sales of chemical and biological detectors will reach almost $3 billon in 2009. Both sets of detection equipment have strengths and weaknesses. When used in concert, an attack is statistically more likely to be detected. However, with funding always a factor the end-user and manufacturers must be able to identify which of these technologies, if not both, will best address the detection needs." (Farr, 2004) Farr goes on to state that understanding this type of equipment requires that the "threat be understood." (2004) Chemical attack are horrendous however even deadlier are attacks using biological weapons requiring only "microscopic quantities" to kill millions of people. Biological weapons are stated to be an unlikely option "for all but nation-states." (Farr, 2004) Furthermore, it often takes days and weeks or sometimes much longer for the individual to have symptoms related to exposure. Farr states that the greatest fear is that "a suicide bomber will infect him/herself with a biological agent that takes a couple of days to manifest and fly to the airport of London, New York, Paris etc... This would allow a terrorist to spread a virus worldwide without having to plan an attack, weaponize the agent or develop a mode of delivery." (Farr, 2004) the market for biological weapon detection was in excess of $340 million in 2003 according to "...Frost & Sullivan's annual report." (Farr, 2004)

I. BIOLOGICAL DETECTION EQUIPMENT

Biological agents may potentially "spread across an entire population, thereby affecting the entire region or country." (Farr, 2004) Farr states that biological detection strategy is far more complicated than chemical detection because the equipment must have the capacity to "detect and correctly analyze microscopic elements that occur naturally in the environment." Additionally stated in Farr's work is that."..biological detection equipment should first and foremost be deployed at international points of entry, airports, seaports and border-crossings."(2004) in fact, Farr reports a pilot program study being conducted by Sandia national laboratory at San Francisco's International Airport with "prototype biological detection equipment." (2004) Information garnered in this study will be applied at other airports for providing a means of protection and is stated to be one that will be used "in a national strategy to protect the airports. Additionally, detectors should consist of a nationally integrated grid with large cities receiving some sort of integrated detection equipment. Bio-detectors must be able to alert authorities of an attack so that it may be contained." (Farr, 2004) Stated to be the primary driver of this market is the U.S. Biowatch program "operating in 30 cities..." And monitoring data, which is collected in "more than 4,000 atmospheric sampling stations that act as an early warning system for any airborne pathogens." (Farr, 2004) the 2005 budget is stated to have allocated an additional $129 million for this program and Biolog is stated to have received a grant award in the amount of $2.28bn from the "...National Institute of Allergy and Infectious Disease to fund the development of advanced detection and identification methods for bacteria including those that could be used in act of bio terrorism."(Farr, 2004)

The work of Hood (1999) entitled: Chemical and Biological Weapons: New Questions, New Answers published in the Research Highlights of the journal of Environmental Health Perspectives states that the issues perceived as the "most troubling...are raised by Sharon Reutter of the Toxicology Team at the U.S. Army Edgewood Chemical Biological Center at Aberdeen Proving Ground, Maryland, in her article "Hazards of Chemical Weapons Release during War: New Perspectives." Reutter's thesis is that today's potential uses of chemical weapons have changed dramatically since the compounds were first developed, and that scientific analysis of the materials and their toxicological effects must change to accommodate those contemporary scenarios." (Hood, 1999) Reutter is noted as having stated: "...the way we look at the toxicity of the chemical agents has changed. And people don't realize that when they see some of the reports that have come out lately. it's not that anything has changed about the agents, but we're asking different questions, and that makes the answers different. When the original research and development work was conducted people were designing weapons of war, and they were trying to figure out how much killed how quickly -- or how little it would take to kill how quickly, because you obviously want something the more potent the better, within limits." Most of the research was done on animals. A few studies, using low doses to produce relatively mild effects, were performed in humans -- usually young, healthy males, who were then the likely targets of a chemical attack. Although those data are invaluable, they are inadequate to answer the new questions arising from the new perspectives." (Hood, 1999) it is Reutter's belief that that possibility in today's world for exposure to these types of weapons is much higher than in the past. Hood (1999) concludes in the report the fact that: "New targets have brought about a need for new data." (Hood, 1999) the work of Burrows and Renner states that further development of BW detection equipment is needed as well as testing of the agents themselves to make determinations relating to the agent's tolerances for disinfection using chlorine and other methods and that "studies of the efficacy of the various point-of-use purifiers in removing in inactivating BW agents" is needed. (Hood, 1999) in a 2007 Department of Defense briefing biological weapons and detection, equipment are reviewed and questions answered. Stated in this briefing by 'Reeves' is that "since the Gulf War, we've put out actually five new biological detectors, and Portal Shield is one of them. it's a semi-automated detector that we use at fixed sites around ports, airfields, bases. It can detect up to 10 different biological agents and give you a result within 15 minutes of detection as to what that agent is." (Doesburg, 2003)

Bio-Detection Process: A Four-Step Process

The work entitled: Biological Detection System Technologies: Technology and Industrial Base Study - a Primer on Biological Detection Technologies published by TRW Systems and Information Technology Group in February 2001 for the North American Technology and Industrial Base Organization (NATIBO) relates what is stated to be 'candidate biological detection technologies' and states that the bio-detection process is one that is "relatively complex" and is a four-step process as follows:

1) Cueing - Is a suspicious aerosol cloud present?

2) Detection - is a biological substance present in the aerosol cloud?

3) Discrimination - Is a biological agent present; and 4) Identification - What is the biological agent. (NATIBO, 2001)

Sampler/Collector Types

In this process once having been triggered, other subsequent steps are initiated. There are stated to be several sampler or collector types used in detecting biological agents, which include those as follows:

1) Biological sampling techniques must "preserve and not harm or alter the collected sample";

2) Most biological detection and identification technologies require a sample that is in liquid form requiring the collection be taken from an aerosol or particulate onto a liquid; and 3) Since response time is a critical factor, the liquid sample must be highly concentrated and quickly available for analysis." (NATIBO, 2001)

Another type of collection is the 'cyclone' collector which is "an inertial device" used in common applications of industry in which particles are removed from airflows that are large. The blower system forces the air which is laden with particles into "a tangential inlet at the top. The particle laden air stream forms an outer spiral moving downward toward the bottom of the open-based cone. Larger particles are collected on the outer wall due to the centrifugal force, and slowed due to aerodynamic effects and fall out the bottom outlet in the center of the top." (NATIBO, 2001) Water is then sprayed on toward the outer walls facilitating in the collection and preservation of the particles. The conventional impactor operates through a method in which particles are accelerated through a nozzle with the air stream "directed against an impaction plate maintained at a fixed distance from the nozzle. The plate deflects the flow, and the larger particles are unable to follow the fluid streamlines and thus impact the plate. Smaller particles follow the fluid streamlines and exit the sample." (NATIBO, 2001)

The method of operation of a "bubbler or impinger" is through "drawing aerosols through a current inlet tube and jet. Usually the jet is submerged in the liquid contained in the sampler." (NATIBO, 2001) the aerosol particles become capture din the base of the jet by the surface of the liquid as the air moves through the liquid. Collection of the smallest of the particles is enabled by a "small critical orifice causing the flow to become sonic." (NATIBO, 2001)There are designs that also form bubbles in the liquid as air leaves the jet which is fitted. The Variable Particle-Size Impactors are stated to generally have."..multiple stages" in which "each stage contains a number of precision-drilled orifices that are appropriate for the size of the participle to be collected in that stage and orifice sizes decrease with each succeeding impactor state." (NATIBO, 2001) as particles in the air are collected in the instrument, they are forced toward the surface collector by the orifices of the jet. Particles uncollected at that stage follow the air stream around the collection surfaces edge to the next stage.

Two Types of Triggers in Bio-Sensing Technologies

Technologies used in detection and triggering include: (1) a simple trigger; and (2) a complex trigger. The simple trigger is stated to "...respond to an increase in the atmospheric particulate background count or concentration. Once the threshold is breached, it activates the more complex and precise detector element to determine the nature of the suspected agent." (NATIBO, 2001)

Flow Cytometry

Cytometry is stated to refer "to the measurement of both the physical and chemical characteristics of cells. Flow cytometry refers to this same technique in which the characteristic measurements are made as the cells or other participles, which are present in a moving fluid stream, pass through an interrogation point." (NATIBO, 2001) This technology is a "hybrid technology" in which development in computer processing, optoelectronics, monoclonal antibody production, flurochrome chemistry and laser technology are all combined to make provision of a method that is automated in making analysis of bio-chemical properties. (NATIBO, 2001; paraphrased) This technique is one which "permits characterization and identification of biochemical species within a heterogeneous mixture of organic and inorganic material." (NATIBO, 2001) Flow Cytometry enables the measurement of the "physical and chemical characteristics of cells or particles." The following table shows the structural characteristic so biological cells measurable by flow cytometry.

Structural Characteristics of Biological Cells Measurable by Flow Cytometry

Source: (NATIBO, 2001)

Stated as advantages of using flow cytometry for biological sensing are the advantages as follows:

1) Fast sample preparation and analysis;

2) Single particle analysis;

3) Detection and identification in one instrument;

4) Significant multiplexing advantages;

5) Easily quantifiable results;

6) Adaptability to high, automated throughput;

7) Simple to operate; and 8) Compact instrumentation. (NATIBO, 2001)

Mass Spectrometry (MS)

Mass spectrometers separate ionized atoms and molecules from each other through using the mass-to-charge ratio differential. Mass Spectrometry is useful for "quantification of atoms or molecules and also for determining chemical and structural information about molecules." (NATIBO, 2001) Mass spectroscopy is a process that re-assembles fragments and then works in a fashion of backing up to bring about a generation of the original molecule. Stated to be the general operation of a mass spectrometer is the creation of "gas-phase ions" and then separation of the ions in space or in time "based upon their mass-to-charge ratio. The process known as resolution is one in which the mass spectrometers power is used in a process of separating ions dependent on their mass-to-charge ratio. Resolutions is defined as follows:

m/m where m is the ion mass and m is the difference in mass between two resolvable peaks in a mass spectrum." (NATIBO, 2001)

The ionization techniques used by mass spectrometers are varied with the various techniques producing different degrees of "fragmentation and organic compounds and therefore producing varying results for analysis." (NATIBO, 2001) Some of the various mass spectrometry techniques include the following:

1) Electron Impact Ionization;

2) Chemical Ionization;

3) Fast Atom Bombardment (FAB);

4) Electrospray Ionization (ESI); and 5) in MALDI in which the analyte is diluted in a solid or liquid matrix which strongly absorbs laser light. (NATIBO, 2001)

The analyzer that mass spectrometers use to quantify the ions by their mass-to-charge ratios are calibrated and there are several types of these analyzers which include the following:

1) Fourier-transform mass spectrometers;

2) Ion-trap mass spectrometers;

3) Time-of-Flight mass spectrometer; and 4) Quadrupole mass filter consisting of four rods. (NATIBO, 2001)

Hand Held Immunochromatographic Assays (HHA)

The Hand Held Immunochromatrographic Assays (HHA) is a "simple, antibody-based assay used to identify biological warfare agents." (NATIBO, 2001) the HHA is not expensive and is a very reliable means of identification of biological warfare agent. Presently the HHA has the capacity to make identification of eight biological warfare threats and four stimulant agents. (NATIBO, 2001) the HHA is very simple to use and instructions state as follows: "...a small quantity of solution containing the suspected agent is placed in a well on the assay. Over a 15-minute period, the solution wicks through the assay where it is successively exposed to different antibodies. The first antibodies flow up the assay as soon as they come in contact with the solution and bind themselves to the specific biological warfare agent, if it is present. A second region of antibodies is moored to the assay's test area, where they immobilize the biological warfare agent (along with the bound antibodies). An enzyme attached to the moored antibody changes the color of a coating on the assay when this antibody binds to the biological warfare agent. A change in the color of this region is evidence of a positive test." (NATIBO, 2001) Presently the Department of Defense is concentrating on development of: (1) Hand-held bio-sensors that detect airborne biological agents with clear signal, affordable and with a low false alarm rate; (2) Ion-detection devices that can continuously monitor the air for BW agents; and (3) Non-intrusive detection of biological agents. (NATIBO, 2001) it is related that there is ongoing development of "several stand-alone detectors." NATIBO, 2001)

The goals set out in this development is the reduction of the "dependence on reagents and size, weight and power requirements of existing systems." (NATIBO, 2001) These technological challenges are presently being addressed in DoD research. Stated as a 'key hurdle' to effective coordination of joint detection systems "is determining how to be collaborate between civilian and military CB detection measures." (NATIBO, 2001) the stated goal of DARPA's Sensor Integration and Modeling for Biological Agent Detection (SIMBAD) program is the development and demonstration of sensor system prototypes for CB agent detection which are "fully integrated and well-characterized." (NATIBO, 2001) SIMBAD is stated to be inclusive of, although not limited to the technologies as follows:

Time-of-flight spectrometers;

Antibody-based sensors;

PCR-based sensor for DNA analysis;

Hyperspectral imaging micro-Raman biochip sensor module;

Biofluorescence LIDAR for triggers and stand-off detection of bioagents;

Micromachinized aerosol collectors; and Sensor network architectures. (NATIBO, 2001)

The following figure shows the biological detection system components as stated in the National Institute of Justice work entitled; "An Introduction to Biological Agent Detection Equipment for Emergency First Responders."