The Honorable Carl Ford, Assistant Secretary of State for Intelligence and Research detailed many of the reasons state and nonstate actors might choose to use BW. He said,
“Virtually all the equipment, technology and materials needed for
biological agent research and development and production are available on the
open market as well as in the secondary markets of the world. Vaccine research
and disease treatment require essentially the same equipment. Because biological
weapons are relatively cheap, easy to disguise within commercial ventures, and
potentially as devastating as nuclear weapons, states seeking to deter nations
with superior conventional or nuclear forces find them particularly attractive.
Therefore BW will probably continue to gain importance since it can kill or
incapacitate military forces or civilian populations, while leaving
infrastructure intact but contaminated.”(48).
The Honorable Carl Ford
articulated several of the advantages BW have for acquisition. There are also
disadvantages that make them less desirable for state/nonstate actors.
Advantages
BW are weapons of mass destruction (WMD). Having a WMD can accomplish
certain objectives for a state/nonstate actor. WMD have been used by states over
the years to tip the balance of power in their favor and to deter other
countries from attacking them. In 1970, the World Health Organization estimated that 50 kg of
anthrax released over a city of 5 million could sicken 250,000 and
kill 100,000. (49) A U.S. Congressional Office of Technology
assessment from 1993 estimated that between 130,000 and 3 million
deaths would follow the release of 100 kg of anthrax. Some say this
number of deaths would match that of a hydrogen bomb (50).
Most BW equipment is dual-use, easy to obtain and can be disguised as a
reasonable purchase for a legitimate business. The equipment used to grow
and maintain BW is commonly available and is used everyday by research
laboratories, hospital laboratories, and the fermentation and biotechnology
industry. Large-scale production of BW can be conducted in equipment routinely
used by the fermentation and biotechnology industry. All of the equipment has
dual-use capabilities in that it can be used for military and civilian
activities. This equipment is very expensive and almost all of the equipment
needed to produce BW is available on the open market. The Japanese Aum Shinrikyo
group used front companies to purchase most of their equipment. If a front
company stated they were in a business requiring fermentation, like a brewery or
drug company, few would think any of the orders for growing, maintaining and
large-scale production equipment would be out of the ordinary.
Detection and identification of BW is relatively slow and expensive. Current
detector technology, for BW, works best in terms of "detect to
respond" or "detect to react" rather than "detect to
warn." Most detectors only respond when the threat is directly present.
Alerting civilians, first responders or troops to the immediate danger is
usually the only goal of a detector (44).
Garments (respirator, gloves, suit covering arms and legs) routinely worn by
the military during a chemical weapons attack will protect a person from a BW
attack. Unfortunately, there is currently no rapid means of detection and
identification of a BW release that would give a person in the immediate area of
the BW release enough time to put on the protective garments. An aerosol of BW
is thought to be invisible and has no smell or taste. An attacker could release
the BW leave the area and no one would know. Without a means of early detection
it could take days to weeks before people reported any illness. Since many of
these BW cause rarely seen illnesses, misdiagnoses and delays in care could
result in more spread of contagious illnesses and more lethal events in infected
patients.
There are currently two types of BW detectors: remote detectors (cloud
detection) and point detectors (particle size, immunological, nucleic acid).
Remote detectors can be used to detect BW clouds. If a BW is released as an
aerosol it forms a cigar shaped cloud when released from a plane or moving
vehicle that is usually quite different in shape from naturally occurring
clouds.
Remote Detectors
One way to detect these BW clouds is through the use of Doppler radar. Using
reflected radio waves a cloud and its shape can be detected. Another remote
detector called "Laser Identification and Ranging" or LIDAR uses
higher energy light waves to detect clouds. These detectors can distinguish a
nonbiological cloud from a biological one by detecting certain organic compounds
in the biological cloud (tryptophan, NADH, ATP, riboflavin). There are both long
range and short-range devices. The short-range devices can obtain more
information. The long-range detectors can alert and warn people of a cloud
coming into the area. Possible false positives include clouds created due to
pollen, molds, organic excreta and certain organic agricultural fertilizers. The
military has developed both short – and long-range LIDAR detectors (44).
None of the detectors mentioned above can tell what BW is being used or if a
previous BW release has occurred and has settled on the ground. Recent work
using laser-induced breakdown spectroscopy (LIBS) may become such a detector. The
lasers used in the instrument breakdown the biological agent in a cloud or on
the soil and then separate the various breakdown products using spectroscopy to
identify the biological agent in the cloud. Some believe this instrument may
also be able to distinguish between a pollen cloud and a BW cloud. There is
still much to do to prove this technology will work in the field.
Point Detectors
These detectors require it to be inside the BW cloud to obtain a sample.
There are two basic types of point detectors: particle size and microorganism
identification.
Aerosol particle size detectors
With most aerosolized BW the biological agent must get down into the alveoli of the lungs to cause an infection. Particles from 0.5 to 5 microns are inhaled and make it to the alveoli. Particles smaller than 0.5 microns will not stay in the alveoli but be eliminated upon exhalation. To remain suspended in the air the particle can’t be too large. Particle larger than 100 microns will rapidly settle to the ground. Aerosol particle size detectors can determine the size of the particles in a cloud. If the particles are too small or too large it is unlikely that they would be an effective BW. These detectors do not identify what biological agent is in the cloud they currently only tell an operator if the particle size is what one would expect of a BW cloud.
At least four basic approaches have been used so far to detect and identify BW: nucleic acid, immunological methods, mass spectrometry and surface acoustical wave sensors. Nucleic acid approaches seek to detect the presence of a BW by looking for its genetic material. One example of a nucleic acid method is called real-time PCR (real-time polymerase chain reaction). Real-time PCR uses a heat resistant DNA polymerase and small pieces of DNA (probes) that are complimentary to the beginning and the end of a gene to make many copies of one of the biological agent’s genes. While the copies are being made a fluorescent dye is incorporated into the new gene copies. When enough of the gene copies have been made a detector in the real-time PCR machine tells the operator that a positive result has been obtained. This technique can detect between 1 and 100 bacterial cells in a sample in about an hour. Unfortunately, the reagents and the machine used to do real-time PCR in are expensive. This technique is also labor intensive, requires highly trained personnel and works best when pure samples of the biological agents are used. If these obstacles can be overcome real-time PCR might not only be useful in detecting BW but also in rapidly identifying organisms that cause naturally occurring human disease.
DNA microarrays or “chips” are also being tested to see if they can detect BW. The advantage of this technology is that on one chip all of the BW thought possibly in the sample could be tested for. This technology is very expensive, requires highly trained professionals and takes several hours to perform.
There are several different immunological methods used to detect BW. Most of these methods are 10 to 1000 times less sensitive than nucleic acid methods. However, they can take less time than nucleic acid techniques and are usually less expensive. The commercially available Smart Tickets (Response Equipment Company, Abingdon, Maryland; http://www.r-e-c.com/prod_bwdetect.html) are one example of an immunological method that can detect several different BW. It requires at least 2000 organisms to give a positive result. Once enough organisms have been acquired it takes 5-15 minutes before the Smart Ticket can detect a BW release. Each card can only detect one particular BW so several cards may have to be used at the time of a BW release. A recent CDC report indicates that these detectors can in some situations give false positive results by detecting nonpathogenic microorganisms that are closely related to the BW. (http://www.bt.cdc.gov/agent/anthrax/environment/handheldassays.asp)
The biological detector portion of the U.S. military's Biological Integrated Detection System (BIDS) includes immunoassay-based sensors as part of its suite of detectors. It is reported that their BIDS system can detect up to 10 different BW.
Mass spectrometry involves fragmentation of enzymatic metabolites of the biological agent followed by separation of the fragmentation products by their molecular weight. Each biological agent has a relatively unique fragmentation pattern. This technology is relatively quick however it also is very expensive and requires highly trained professional.
Surface acoustical wave systems are based on
piezoelectric materials (those that produce an electrical current when subjected
to pressure or mechanical stress) coated with antibodies or nucleic acid
sequences reactive with or complimentary to BW. If the antibody or nucleic acid
sequence on the piezoelectric crystal binds to a BW in the sample a change in
the mass on the surface of the crystal occurs that then changes the frequency at
which the crystal vibrates under an electric current. This change in frequency
is detected and alerts the operator to the presence and, perhaps, the identity
of the BW agent. This technology is not very sensitive and can detect 105-106cells.
Contagious BW can spread the infection rapidly. Several BW are not
spread person-to-person (ex. anthrax). However, those that are can pose a
significant problem to public health officials trying to contain the spread of
the disease. If undetected and misdiagnosed a contagious BW could also spread
rapidly to other nations considering that a person can fly almost anywhere in
the world in 24 hours. Smallpox is a contagious BW. Smallpox has been produced
as a BW in a number of countries however no state/nonstate actor has released
smallpox as a BW.
A natural outbreak of smallpox in Yugoslavia during 1972 may demonstrate how
rapidly a contagious unidentified infection can spread. No smallpox case had
been reported in Yugoslavia since 1927. The physicians in the country had no
experience in diagnosing this disease. The index case was a 30-year-old
schoolteacher who became ill and was given penicillin in the hospital. He got
worse and was moved to another hospital, then to a district hospital and then to
the capital city’s hospital. At the hospital in the capital he was taken to an
intensive care unit where he died. By the time the schoolteacher had died he had
already infected 35 others in the hospitals he stayed at. Before they could
figure out what the cause of the mysterious disease was 150 cases of smallpox
had been reported. Other countries sharing borders with Yugoslavia closed their
borders. There were also about 10,000 people who had had some contact with the
150 smallpox cases. They had to be quarantined. To quarantine these people they
took over hotels and apartment buildings, cordoned off the buildings and police
surrounded the buildings to keep people from leaving or entering (7).
It can be difficult to separate naturally occurring outbreaks from a BW
release. Many naturally occurring disease outbreaks occur each year with
some biological agents found on BW lists. Every year thousands of people get
diarrhea from a variety of organisms like Salmonella. Some members of the
Rajneeshees, followers of Bhagwan Shree Rajneesh, placed a bacterium called Salmonella enterica
serotype Typhimurium in food at various Dalles, Oregon restaurants in
1984. The large epidemic of diarrhea brought in several health department
officials who blamed the outbreak on unsanitary practices of the food handlers.
It was not until a year later that previous members of the group admitted to
police that members of the Rajneeshee group had contaminated the local
restaurant salad bars with a BW. What looked like a natural outbreak due to
unsanitary food handler practices turned out to be a BW release that made 751
people sick (5).
BW leave the infrastructure intact and may require significant amounts of
time and money to decontamination. BW do not damage buildings nor do they
appear to cause long-term damage to the environment. This gives state/nonstate
actors that would want to takeover an area after a BW release certain advantages
in that they could after decontaminating the area occupy it relatively quickly.
This is especially the case for BW that degrade rapidly like the smallpox virus.
Other BW like anthrax will contaminate an area for decades (47). To inhabit it
again requires expensive decontamination procedures. Contaminating an area that
a state/nonstate actor is not particularly interested in occupying would cost
the victims of the attack a large amount of time and money if they wanted to
reoccupy the area.
New and emerging biological agents are being discovered nearly every year
and could be added to an already long list of BW. As humans intrude into
areas few people have been before they can sometimes acquire “new” diseases.
Some of these diseases are fatal. One example of such a disease is Rift Valley
Fever (RVF) caused by RVF virus. The first epidemic of RVF occurred in 1987 in West Africa and was linked
to construction of the Senegal River Project Dam. The project caused flooding in
the lower Senegal River area. Normally mosquitoes carried the virus from animal-to-animal in this river valley. However, when the animals and their mosquitoes
were chased out of the river valley by rising water they settled near areas
populated by humans. The RVF virus infected mosquitoes that rarely took a blood
meal from humans now had many more humans to bite resulting in the first human
epidemic of RVF (51). RVF can cause death in 1% of humans infected by the virus.
This previously unknown virus is now on the list of BW.
BW can be genetically and antigenically modified. With the advent of molecular genetics microorganisms can be altered to make them even more formidable weapons. Many but not all of the following scenarios are speculative and not all potential scenarios are listed. Genetically engineered pathogens could be designed to have any or all of the following (23):
BW are not cheap but many feel that they are cheaper than other weapons.
To affect 1 square kilometer, it is estimated that it would cost about $2000
using conventional weapons, $800 using nuclear weapons, $600 using chemical
weapons and $1 using BW. (52)
If released in the air the spread of the BW is dependent on climatic
conditions. Release of a BW in the air is dependent of changing climatic
conditions. Winds can change and drastically affect how far an aerosol will
travel. BW are also sensitive to sunlight. Releasing a BW in the middle of a
bright sunny day can kill many of the microorganisms in the aerosol. After
release many BW only last a short period of time in the environment making
timing of the BW release for maximal effect important.
The BW can infect the one who releases the BW if they are not properly
trained and protected. Protection could include being vaccinated or wearing
a respirator (gas mask) and other protective clothing. Someone in a highly
populated area wearing protective clothing might draw some attention possibly
thwarting the BW release. The BW can result in what some call the “Boomerang
effect”. The agent released could with the right wind conditions come back and
infect those that release it.
BW are not cheap to produce. Comparisons can sometimes give false
impressions. BW according to some reports are relatively cheap to produce but
the comparisons are with more expensive weapons systems. It would still take
millions of dollars to get a BW weapon plant up and running. Most nonstate
actors do not have the resources to build such a program.
There are different strains of each biological agent and they can become
less lethal. Biological agents are relatively complex living organisms. They
can undergo spontaneous mutation or lose genes that would make them less lethal.
One example is the Sterne strain of the bacterium, Bacillus anthracis,
which causes anthrax. It is a strain that was developed in 1935 that when
cultured over time lost its ability to produce a protective outer capsule when
it lost the plasmid that coded for the capsule. (53) The main reason many
believe that the Japanese group Aum
Shinrikyo did not infect the citizens of Tokyo with anthrax was that their
strain of Bacillus anthracis was not very pathogenic. There are also
different strains of viruses (smallpox) that are more lethal than others. Just
getting a particular microorganism does not guarantee that it will cause
disease. The microorganism must produce the right factors to cause disease. Even
if a pathogenic strain is acquired maintaining its ability to cause disease is
not easy and requires some experience and training.
© 2005 Neal Chamberlain. All rights reserved.
Site Last Revised 11/29/06
Neal Chamberlain, PhD. A. T. Still University of Health Sciences/Kirksville
College of Osteopathic Medicine.
Site maintained by: Neal R. Chamberlain PhD.: nchamberlain@atsu.edu