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What are biological weapons?
When have they been used?
How can they be defended against?
Biological weapons and international law
Biological warfare is the deliberate spreading of disease amongst humans, animals, and plants. Biological weapons (BW) introduce a bacteria or virus, combined with a delivery mechanism, into an environment for hostile purposes, that is not prepared to defend itself from the intruder. As a result, this agent can become very effective at killing plants, livestock, pets, and humans. There are a huge variety of genetically or traditionally modified bacterias and viruses to withstand antibiotics, that could be used as biological weapons, but some of the most common types today are bacteria, rickettsiae, viruses, toxins, and fungi.
Deadly and Cheap
When compared to the cost of a nuclear weapon programme, biological weapons are extremely cheap. It is estimated that 1 gram of toxin could kill 10 million people. A purified form of botulinum toxin is approximately 3 million times more potent than sarin, a chemical nerve agent. As a comparison, a SCUD missile filled with botulinum toxin could affect an area of 3700 sq.km, an area 16 times greater than could be affected with sarin.
It is important to note that while it is relatively cheap to produce the biological weapon agents in large quantities, sophisticated weapons are slightly more difficult to develop and produce. For example, when a missile is flying it gets very hot, and biological agents are killed. Therefore, the missile has to be fitted with a cooling system. In addition, storing biological weapon agents requires much effort, due to the quick decay of many of these sorts of agents. However, as far as weapons of mass destruction are concerned, biological weapons are relatively cheap to develop and produce. In one analysis, the comparative cost of civilian casualties is "$2,000 per square kilometer with conventional weapons, $800 with nuclear weapons, $600 with nerve-gas weapons, and $1 with biological weapons." Not surprisingly, biological weapons have long since become known as the poor man's atom bomb.
Contemporary concerns about biological weapons do not simply involve possession or non-possession of weapons. Instead, concerns primarily involve the degree to which states have the capacity and intent to threaten or perpetrate a biological attack, a concern that is particularly relevant when it comes to countries’ biodefense programmes. Any state with a reasonably advanced pharmaceutical and medical industry has the capability of mass producing biological weapons. This fact also leads to problems with determining what countries have BW programmes. Anything from a piece of fruit to a ballistic missile could be used to deliver a biological weapon to a target. Along with this is the fact that with certain organisms, only a few particles would be needed to start an infection that could potentially cause an epidemic. Conventional weapons explode once and are finished. With a few particles of Hanta virus many thousands of people could become carriers that infect thousands more people.
The “new era of biology” emerging over the last couple of decades has been characterised by significantly accelerated scientific and technological developments, and the convergence of biology with mathematics, engineering, chemistry, quantum mechanics, computer science, and information theory. While these developments generally improve the human condition, they also have misuse potential. Biotechnology know-how and equipment diffuse ever more widely with new tools like wikis, blogs and microblogs—a trend set to continue and expand dramatically in the coming years. As a consequence, individuals, states, and non-state actors have new opportunities to exploit readily available technology.
New developments in biotechnology with misuse potential include: gain-of-function technologies, where potentially pandemic pathogens are deliberately created in the lab; synthetic biology where biological systems are engineered or redesigned; gene editing technologies where DNA is manipulated; and so-called DNA origami, where nucleic acid strands are folded into designed shapes and structures, sometimes with “built-in” ability to perform specific mechanical functions.
When have biological weapons been used - a short history
The first recorded use of biological agents is the Romans using dead animals to foul the enemies water supply. This had the dual effects of decreasing enemy numbers and lowering morale.
1346-1347 - Mongols catapult corpses contaminated with plague over the walls into Kaffa (in Crimea), forcing besieged Genoans to flee. Some historians believe that this event was the cause of the epidemic of plague that swept across medieval Europe killing 25 million.
1710 - Russian troops allegedly use plague-infected corpses against Swedes
1767 - During the French and Indian Wars, the British give blankets used to wrap British smallpox victims to hostile Indian tribes.
1916-1918 - German agents use anthrax and the equine disease glanders to infect livestock and feed for export to Allied forces. Incidents include the infection of Romanian sheep with anthrax and glanders for export to Russia, Argentinian mules with anthrax for export to Allied troops, and American horses and feed with glanders for export to France 1937 - Japan begins its offensive biological weapons program. Unit 731, the BW research and development unit, is located in Harbin, Manchuria. Over the course of the program, at least 10,000 prisoners are killed in Japanese experiments.
1939 - Nomonhan Incident - Japanese poison Soviet water supply with intestinal typhoid bacteria at former Mongolian border. First use of biological weapons by Japanese.
1937 - Japan begins its offensive biological weapons program. Unit 731, the BW research and development unit, is located in Harbin, Manchuria. Over the course of the program, at least 10,000 prisoners are killed in Japanese experiments.
1940 - The Japanese drop rice and wheat mixed with plague-carrying fleas over China and Manchuria
1942 - U.S. begins its offensive biological weapons program and chooses Camp Detrick, Frederick, Maryland as its research and development site.
1945 - Only known tactical use of BW by Germany. A large reservoir in Bohemia is poisoned with sewage.
1951 - In a test of BW dispersal methods, biological simulants are sprayed over San Francisco.
1966 - The United States conducts a test of vulnerability to covert BW attack by releasing a harmless biological simulant into the New York City subway system.
1969 - President Nixon announces unilateral dismantlement of the U.S. offensive BW program.
1970 - President Nixon extends the dismantlement efforts to toxins, closing a loophole which might have allowed for their production.
1978 - In a case of Soviet state-sponsored assassination, Bulgarian exile Georgi Markov, living in London, is stabbed with an umbrella that injects him with a tiny pellet containing ricin (a highly toxic, natural protein).
1979 - Outbreak of pulmonary anthrax in Sverdlovsk, Soviet Union.1992- Russian president Boris Yeltsin acknowledges that the outbreak was caused by an accidental relase of anthrax spores from a Soviet military microbiological facility.
1985-1991 - Iraq develops an offensive biological weapons capability including anthrax, botulium toxin, and aflatoxin.
How can biological weapons be defended against?
Biological defense may be divided into the following categories: prevention, protection, detection, treatment, and decontamination.
Prevention may take several forms. In the case of biological warfare, international disarmament and inspection regimes may deter production and dissemination of biological warfare agents. Intelligence assets may indicate potential threats and allow for preventative action to be undertaken.
Protection against biological warfare agents is limited. Protective suits, clothing, gas masks and filters may provide limited protection for short periods of time. However, the persistence of biological agents such as anthrax makes such protections mainly useful for military personnel and first responders. Anthrax can remain active and potentially lethal for at least 40 years. It should be noted that anthrax is an exception, as most other agents do not live that long. In addition, vaccination is a form of protection, which may provide substantial protection against naturally occurring agents, although vaccines often provide limited or no protection against genetically engineered variants designed to defeat such vaccines.
Detection. During the Gulf War, US and allied forces suffered from a lack of reliable biological agent detection systems. Subsequently, a number of detection systems have been developed. Often it takes from a few hours to a few days to detect exposure to a biological weapon. However, advances in biotechnology will help develop improved and quicker detectors. Current detectors include: SMART (Sensitive Membrane Antigen Rapid Test) JBPDS (Joint Biological Point Detection System) BIDS (Biological Integrated Detection System) IBAD (Interim Biological Agent Detector). Treatment options after infection depend on whether or not the infectious agent is identified. If not identified, massive doses of antibiotics may be given in hopes that something may work. Treatment of victims of biological warfare largely depends on the establishment and maintenance of a good healthcare system.
Decontamination. Unlike chemical weapons, which disperse over time, biological agents may grow and multiply over time. Anthrax can remain active in the soil for at least 40 years and is highly resistant to eradication. However, the anthrax contaminated Gruinard Island in the UK was decontaminated, suggesting that decontamination is possible, using chemicals, heat, or UV rays.
Biological weapons and international law
Using biological and chemical weapons was condemned by international declarations and treaties, notably by the 1907 Hague Convention (IV) respecting the laws and customs of war on land. Efforts to strengthen this prohibition resulted in the conclusion, in 1925, of the Geneva Protocol, which banned the use of asphyxiating, poisonous, or other gases, usually referred to as chemical weapons, as well as the use of bacteriological methods of warfare. The latter are now understood to include not only bacteria, but also other biological agents, such as viruses or rickettsiae, which were unknown at the time the Geneva Protocol was signed. However, the Geneva Protocol did not prohibit the development, production, and stockpiling of chemical and biological weapons. Attempts to achieve a complete ban were made in the 1930s in the framework of the League of Nations, with no success.
The prohibition of chemical and biological weapons appeared on the agenda of the Eighteen-Nation Committee on Disarmament in Geneva (now called the Conference on Disarmament) in 1968. One year later, the United Nations published an influential report on the problems of chemical and biological warfare, and the question received special attention at the UN General Assembly. The UN report concluded that certain chemical and biological weapons cannot be confined in their effects in space and time and might have grave and irreversible consequences for humans and nature. This would apply to both the attacking and the attacked nations. Due to interest in the topic in the end of the 1960s, the Biological and Toxin Weapons Convention was signed in 1972 and entered into force in 1975.
The Biological and Toxin Weapons Convention
The Biological and Toxin Weapons Convention (BTWC or BWC) entered into force in March 1975 after 22 governments ratified it. It was the first multilateral disarmament treaty banning an entire category of weapons of mass destruction. The Convention, about four pages long, bans the development, production, stockpiling, and acquisition of biological agents or toxins of any type or quantity that do not have protective, medical, or other peaceful purposes, or any weapons or means of delivery for such agents or toxins. Under the treaty, all such materiel is to be destroyed within nine months of the Treaty's entry into force. The BWC currently has 182 states parties and five signatory states. Since the entry of the Convention, eight review conferences have taken place. 125 states parties participated in the Eighth Review Conference in November 2017.
The rapid developments in the life sciences with dual-use dimensions in the past years have pushed the BWC back into the centre of the disarmament regime. The greatest challenge for the Convention is therefore its ability to keep pace with these developments and ensure the continued international norm against the use of BW be upheld. With the objective of strengthening the BWC’s institutional capacity, the Eighth Review Conference in 2017 decided to hold yearly Meetings of States Parties (MSPs) and Meetings of Experts (MXs) in the inter-sessional period until 2020. The MXs have yielded rich discussions and could give impetus to the further fleshing out of potential areas of common understandings and to identifying concrete actions but so far, states could not agree on a common path forward.
The BWC does not have a verification mechanism for monitoring global sources of dangerous pathogens but it has politically-binding confidence-building measures. It further mandates that states parties consult with one another and cooperate, bilaterally or multilaterally, to solve compliance concerns. The BWC allows states parties to lodge a complaint with the UN Security Council (UNSC) if they believe other member states are violating the Convention. However, the UNSC’s power to investigate such complaints has never been invoked. Recently, a number of states parties have piloted peer reviews on a voluntary basis, see for example here, here or here.
United Nations Office of Disarmament, The Biological Weapons Convention
The United Nations Office at Geneva, The Biological Weapons Convention
The BioWeapons Prevention Project is a global network of civil society actors and monitors BWC meetings, and issues daily reports.
The Pandora Report is a site run by the George Mason University Schar School of Policy and Government Biodefense Program, and provides a knowledge hub for biodefense related issues.
The Bulletin of Atomic Scientists seeks to bridge the technology divide between scientific research, foreign policy and public engagement since it was founded in 1945, and features a diverse range of articles on bio weapons from renowned experts such as Dr. Filippa Lentzos.
Reaching Critical Will, 2019 Biological Weapons Convention Meeting of States Parties, 11 December 2019
Reaching Critical Will, Report of the 2019 Meetings of Experts of the Biological Weapons Convention, 14 August 2019
Elizabeth Cameron et al., A Spreading Plague: Lessons and Recommendations for Responding to a Deliberate Biological Event, Nuclear Threat Initiative (NTI), 23 June 2019
Natasha E. Bajema, Countering WMD in the Digital Age: Breaking down bureaucratic silos in a brave new world, War on the Rocks, 13 May 2019
David Kushner, Synthetic Biology could bring a Pox on us all, Wired, 25 March 2019
Ryan Morhard, The global economy is woefully unprepared for biological threats. This is what we need to do, World Economic Forum, 5 March 2019
Kolja Brockmann, Dr Sibylle Bauer, and Dr Vincent Boulanin, Bio Plus X: Arms Control and the Convergence of Biology and Emerging Technologies, Stockholm International Peace Research Institute (SIPRI), March 2019
The World Economic Forum, Going Viral, in The Global Risks Report 2019, January 2019
Reaching Critical Will, 2018 Biological Weapons Convention Meeting of States Parties , 18 December 2018
Jesse Kirkpatrick et al., Editing Biosecurity: Needs and Strategies for Governing Genome Editing, December 2018
Filippa Lentzos, Strengthen the taboo against biological and chemical weapons, Bulletin of the Atomic Scientists, 26 July 2018
Filippa Lentzos, How do we control dangerous biological research?, Bulletin of the Atomic Scientists, 12 April 2018