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Nick Barba
Dr. LeFebvre and Master Doctor
Cluster 7: Biomedical Sciences
19 July 2015
Bioterrorism: Biological Agents
Abstract: How biological agents are used as weapons of terror, how they affect
the human body, and what different symptoms and illnesses each different agent causes
will be explained throughout this essay. Smallpox, anthrax, bubonic plague, and
botulism are some agents which are highly likely to be utilized in a biological terrorist
attack.
The intentional release of biological agents such as bacteria, viruses, or other germs is
known as bioterrorism. Much more different than conventional weapons, which use physical
forces, bullets, and explosives to damage human life, biological weapons harness the power of
certain natural agents that can make humans become sick and/or die. Biological weapons are far
more devastating than most conventional weapons and must be considered more often as a
serious threat to national security. It is very likely that they may be used in the future because
these weapons are becoming easier to hide and can now be cheaper than conventional weapons.
There are many different agents that can be used as a biological weapon which have
varying effects on victims and different characteristics, which is why there are different
categories for distinguishing the different biological agents. A, B, and C are the different
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categories every biological warfare agent belongs to. The different categories are based on their
deadliness and ability to spread. Category A agents are the most easily disseminating and are
highly infectious, characterized by high mortality rates (Zubay 3). Category B agents are
considered lower because they have lower mortality rates and can be treated more easily
(Zubay 3). Agents that fall within category C are emerging pathogens that are considered to
have a potential for weaponization due to potentially high morbidity and mortality rates (Zubay
3).
There are three main ways to deploy a biological weapon. The most effective method
would be to create an aerosolized version that would be inhaled by victims (Alibek, Lobanova).
This method would be used to cover as much area as possible. Military scenarios of this method
include medium-range bombers equipped with spray tanks capable of covering more than 1,000
square kilometers; the number of people that could be reached within that space in a heavily
populated area would be tremendous (Alibek, Lobanova 41). Another method of deployment is
contamination of food and water supplies but this limits the choice of agent to one that can infect
the victim through the intestinal tract (Alibek, Lobanova 41). Water contamination is the least
effective because of water filtering systems and also, the agent could be diluted within the huge
amount of water in city water systems. The final main tactic would be to release infected vectors
which carry the agent and pass it on to the victim via biting. Possible vector candidates include
ticks, fleas, or mosquitos- these are prime vector candidates because they can easily get on
people and bite them, infecting them with the biological agent.
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There are a few pathogens which would be the “go to” choice for a terrorist looking to
use a biological weapon. Poxviruses are the largest and most complex viruses that infect humans.
One major agent, very effective as a weapon because of its virility and uniqueness to humans is
the Variola virus, or smallpox. In fact, smallpox has the greatest potential for a biological
weapon due to its clinical and epidemiological properties (Kutzler 68). On another note, the
smallpox virus has been eradicated in the United States and most of the world, so the virus would
need to be reintroduced somehow, which is possible because certain laboratories still have
possession of the virus. One reason why smallpox poses such a huge threat is that smallpox
vaccination halted about 35 years ago; therefore, in our society there are generations of younger
people who are not vaccinated against smallpox, leaving many susceptible to an attack if
smallpox were to be reintroduced. The virus itself can survive in aerosol form for 24 hours and
is highly infectious in small doses (Kutzler 69). It can also be produced in large quantities,
stored stably, transported, and can be transferred from person to person. This means that if there
were to be an outbreak in a densely populated area, an epidemic could very easily erupt.
Smallpox would be an easy agent to reach a mass population, in fact according to Kutzler,
former soviet scientists successfully weaponized smallpox and created missile delivery systems
for the virus. So a terrorist group could strike with biological weapons from different continents
if they were to acquire some serious equipment similar to what the soviets designed. It is also
likely that terrorists could acquire these weapons because there are at least 17 nations that have
or have had biological weapons and scientists with expertise in this field are believed to have
been recruited by nations such as Libya, Iran, Syria, Iraq, and North Korea. With unstable
nations like these in possession of biological weapons, it is very possible that they could fall in
the hands of
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dangerous terror groups and be abused. If smallpox were in fact to be used as a biological
weapon in a very populated area such as New York City, many people would catch the virus and
they would most likely pass it on to someone else. Those who catch the virus would first get an
abrupt fever and then possibly a backache, and then once the fever abates, the eruptive phase
begins. Lesions will appear and within 24 hours of the initial appearance of the rash, the entire
body will be covered. Papules form and within about 12 days they shrink back down and scab
(Zubay 240). Respiratory complications can arise as a consequence of secondary viral infections
from the infectious skin lesions (Zubay 241). For fatal cases, death occurs between the 11th and
16th day of the illness (Zubay 241). To note, smallpox could either be delivered by
aerosolization or possibly by suicide carriers. A suicide carrier of smallpox could infect anyone
they interact with; they could walk around an entire city and infect people who would then infect
other people. A real disaster is plausible if a smallpox attack was executed. Aerosolized
smallpox could be released from any pressurized spray device. It is believed that smallpox could
possibly be modified in the lab to enhance its virulence by inserting a certain gene from a
different strain into the smallpox genome. The virus also contains a sinister natural capability of
incorporating foreign virulence factors into its own genome.
Another dangerous agent that is very likely to be used as an agent for a biological
terrorist attack is Anthrax. The bacteria Bacillus Anthracis is highly pathogenic but not very
stable; it cannot survive outside of a host body for more than 24 hours (Zubay 156). When
deprived of nutrients, the bacterium does not die but morphs into a spore which is very resistant
to environmental stresses and can survive for decades. The spores’ resilience makes it very
easily to be picked up by a host and result in the anthrax disease which is observed to have
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mortality rates of up to 80% (Zubay 157). Anthrax is very available as well; its spore presence
in soil around the world makes it such a likely agent to be used in a biological attack. The one
positive aspect for society of the bacteria is that it does not spread from person to person unless
there is direct exchange of bodily fluids, which means that the only people would get the disease
are the individuals directly exposed to the spores (Zubay 158). But still, the spores can easily
reach many people. Before the bacteria can be used as a weapon, it must first be developed into
a weaponized form. Weaponization of the bacteria is a bit of a process though. There are two
methods of deployment: wet or dry. The dry fine powder version is more effective; therefore,
more desirable but depending on the scenario, the wet version may work better. To create a dry
powdered version of the spores, the bacteria has to be grown on a basic medium. Then the
bacteria have to be processed in a fermentation tank so that it will be deprived of nutrients,
causing the bacteria to revert to spore form. The spores then must be separated from the medium
and should be combined with fine dust particles to maintain spore separation in order to ensure
effectiveness (Zubay 164). Anthrax dust is virtually undetectable which makes it a terrific
candidate for a biological weapon (Zubay 157). The spores can then be deployed with letters,
similar to the anthrax attacks in 2001, which when opened, exposes everyone around them to the
aerosolized spores. To deploy the spores with a wet solution, a simple spray bottle can be used
or even crop duster planes to cover large areas but the problem with this method is that anthrax
spores usually do not resuspend into the air once it has settled onto the ground (Zubay 164).
When the spores are finally inhaled, victims usually only show symptoms similar to those of flu
and colds in the first stage (Zubay 148). In the second stage, the victim will start to rapidly be
overwhelmed by the disease- onset of acute dyspnea and cyanosis which is bluish discoloration
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of the skin caused by lack of oxygenated hemoglobin (Zubay 148). Further hemorrhagic
symptoms last for fewer than 24 hours and ultimately lead to death (Zubay 149). The other types
of anthrax infection: cutaneous which is when a spore makes contact with skin and
gastrointestinal which involves a spore being ingested are not as severe as inhalational but can
still be deadly.
Yersinia pestis, known as the plague is a very capable agent to be used as a biological
weapon. It devastated Europe in the 14th century and could potentially do the same to our
present world. Although the plague can now be treated with antibiotics, a widespread attack
would cause mass panic and some deaths could possibly occur if there was a lack of medical
attention for a large population. The organism is very accessible, easy to produce, can be
delivered in aerosol form, and is easily disseminated; this is why the plague is such a dangerous
potential weapon. A small dose of only about 50-100 bacteria is enough to cause pneumonic
plague, an extreme illness with a high mortality rate (Zubay 225). If an outbreak were to occur,
the widespread panic would be extremely difficult to contain. Again, plague would be an
unlikely biological weapon due to our ability to treat it but it is still classified as a category A
agent because it has so much potential to cause serious damage. The most effective tactic to
carry out an attack with plague would be to release infected vectors, such as fleas. Fleas can
travel on small rodents and any other animal which would allow them to come in contact with
people, infecting them by biting and inoculating huge amounts of bacteria into the skin.
The most poisonous substance in the world definitely has a potential for bioterrorism,
being that it derives from a bacteria. Clostridium botulinum produces the toxin botulinum
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neurotoxin, which causes neuroparalytic disease which is known as botulism (Zubay 27). The
botulinum neurotoxin is classified as a category A bioweapon because of its “tremendous
potency and lethality, relative ease of production and transport, and the need for prolonged
intensive care for among infected individuals” (Zubay 27). The bacteria are anaerobic, sporeforming, and they infect mammals and birds. If it were to be used as a biological weapon, then it
would most likely be used in an aerosolized form to cause inhalation botulism or as a deliberate
food contaminant to cause foodborne botulism. Victims of botulism will experience symmetric
descending flaccid paralysis, which is paralysis of the muscles of the tongue, lips, palate,
pharynx and larynx (Zubay 36). They will also experience difficulty in swallowing, double
vision, but the victim remains afebrile and cognitively alert and aware (Zubay 36). The toxin is
so potent; one gram of the aerosolized version could kill up to one million people if dispersed
evenly.
The agents discussed are just a few of many that are very dangerous and could possibly
be used as a biological terrorism attack weapon. Other agents include Tularemia, Ebola Viruses,
Influenza Virus, Hantavirus, Severe Acute Respiratory Virus, Cholera, and Salmonella. They
have interesting ways of defeating our immune systems, and hold the ability to disturb entire
nations as well as cheerleading camps. An understanding and respect for these powerful
pathogens is crucial and the fact that we have these pathogens mostly under control should
definitely be appreciated.
Works Cited
Anderson, Burt, Herman Friedman, and Mauro Bendinelli, eds. Microorganisms and
Bioterrorism. New York: Springer, 2006. Print.
Zubay, Geoffrey L. Agents of Bioterrorism: Pathogens and Their Weaponization. New
York: Columbia UP, 2005. Print.