Biological weapons may be employed in various ways to gain a strategic or tactical advantage over the enemy, either by threats or by actual deployments. Like some chemical weapons, biological weapons may also be useful as area denial weapons. These agents may be lethal or non-lethal, and may be targeted against a single individual, a group of people, or even an entire population. They may be developed, acquired, stockpiled or deployed by nation states or by non-national groups. In the latter case, or if a nation-state uses it clandestinely, it may also be considered bioterrorism.[9]
Biological warfare and chemical warfare overlap to an extent, as the use of toxins produced by some living organisms is considered under the provisions of both the BWC and the Chemical Weapons Convention. Toxins and psychochemical weapons are often referred to as midspectrum agents. Unlike bioweapons, these midspectrum agents do not reproduce in their host and are typically characterized by shorter incubation periods.[10]
Overview
A biological attack could conceivably result in large numbers of civilian casualties and cause severe disruption to economic and societal infrastructure.[11]
A nation or group that can pose a credible threat of mass casualty has the ability to alter the terms under which other nations or groups interact with it. When indexed to weapon mass and cost of development and storage, biological weapons possess destructive potential and loss of life far in excess of nuclear, chemical or conventional weapons. Accordingly, biological agents are potentially useful as strategic deterrents, in addition to their utility as offensive weapons on the battlefield.[12]
As a tactical weapon for military use, a significant problem with biological warfare is that it would take days to be effective, and therefore might not immediately stop an opposing force. Some biological agents (smallpox, pneumonic plague) have the capability of person-to-person transmission via aerosolized respiratory droplets. This feature can be undesirable, as the agent(s) may be transmitted by this mechanism to unintended populations, including neutral or even friendly forces. Worse still, such a weapon could "escape" the laboratory where it was developed, even if there was no intent to use it – for example by infecting a researcher who then transmits it to the outside world before realizing that they were infected. Several cases are known of researchers becoming infected and dying of Ebola,[13][14] which they had been working with in the lab (though nobody else was infected in those cases) – while there is no evidence that their work was directed towards biological warfare, it demonstrates the potential for accidental infection even of careful researchers fully aware of the dangers. While containment of biological warfare is less of a concern for certain criminal or terrorist organizations, it remains a significant concern for the military and civilian populations of virtually all nations.
Rudimentary forms of biological warfare have been practiced since antiquity.[15] The earliest documented incident of the intention to use biological weapons is recorded in Hittite texts of 1500–1200 BCE, in which victims of tularemia were driven into enemy lands, causing an epidemic.[16] The Assyrians poisoned enemy wells with the fungus ergot, though with unknown results. Scythian archers dipped their arrows and Roman soldiers their swords into excrements and cadavers – victims were commonly infected by tetanus as result.[17] In 1346, the bodies of Mongol warriors of the Golden Horde who had died of plague were thrown over the walls of the besieged Crimean city of Kaffa. Specialists disagree about whether this operation was responsible for the spread of the Black Death into Europe, Near East and North Africa, resulting in the deaths of approximately 25 million Europeans.[18][19][20][21]
Biological agents were extensively used in many parts of Africa from the sixteenth century AD, most of the time in the form of poisoned arrows, or powder spread on the war front as well as poisoning of horses and water supply of the enemy forces.[22][23] In Borgu, there were specific mixtures to kill, hypnotize, make the enemy bold, and to act as an antidote against the poison of the enemy as well. The creation of biologicals was reserved for a specific and professional class of medicine-men.[23]
18th to 19th century
During the French and Indian War, in June 1763 a group of Native Americans laid siege to British-held Fort Pitt.[24][25] The commander of Fort Pitt, Simeon Ecuyer, ordered his men to take smallpox-infested blankets from the infirmary and give it to a Lenape delegation during the siege.[26][27][28] A reported outbreak that began the spring before left as many as one hundred Native Americans dead in Ohio Country from 1763 to 1764. It is not clear whether the smallpox was a result of the Fort Pitt incident or the virus was already present among the Delaware people as outbreaks happened on their own every dozen or so years[29] and the delegates were met again later and seemingly had not contracted smallpox.[30][31][32] During the American Revolutionary War, Continental Army officer George Washington mentioned to the Continental Congress that he had heard a rumor from a sailor that his opponent during the Siege of Boston, General William Howe, had deliberately sent civilians out of the city in the hopes of spreading the ongoing smallpox epidemic to American lines; Washington, remaining unconvinced, wrote that he "could hardly give credit to" the claim. Washington had already inoculated his soldiers, diminishing the effect of the epidemic.[33][34] Some historians have claimed that a detachment of the Corps of Royal Marines stationed in New South Wales, Australia, deliberately used smallpox there in 1789.[35] Dr Seth Carus states: "Ultimately, we have a strong circumstantial case supporting the theory that someone deliberately introduced smallpox in the Aboriginal population."[36][37]
World War I
By 1900 the germ theory and advances in bacteriology brought a new level of sophistication to the techniques for possible use of bio-agents in war. Biological sabotage in the form of anthrax and glanders was undertaken on behalf of the Imperial German government during World War I (1914–1918), with indifferent results.[38] The Geneva Protocol of 1925 prohibited the first use of chemical and biological weapons against enemy nationals in international armed conflicts.[39]
World War II
With the onset of World War II, the Ministry of Supply in the United Kingdom established a biological warfare program at Porton Down, headed by the microbiologist Paul Fildes. The research was championed by Winston Churchill and soon tularemia, anthrax, brucellosis, and botulism toxins had been effectively weaponized. In particular, Gruinard Island in Scotland, was contaminated with anthrax during a series of extensive tests for the next 56 years. Although the UK never offensively used the biological weapons it developed, its program was the first to successfully weaponize a variety of deadly pathogens and bring them into industrial production.[40] Other nations, notably France and Japan, had begun their own biological weapons programs.[41]
When the United States entered the war, Allied resources were pooled at the request of the British. The U.S. then established a large research program and industrial complex at Fort Detrick, Maryland, in 1942 under the direction of George W. Merck.[42] The biological and chemical weapons developed during that period were tested at the Dugway Proving Grounds in Utah. Soon there were facilities for the mass production of anthrax spores, brucellosis, and botulism toxins, although the war was over before these weapons could be of much operational use.[43]
The most notorious program of the period was run by the secret Imperial Japanese ArmyUnit 731 during the war, based at Pingfan in Manchuria and commanded by Lieutenant General Shirō Ishii. This biological warfare research unit conducted often fatal human experiments on prisoners, and produced biological weapons for combat use.[44] Although the Japanese effort lacked the technological sophistication of the American or British programs, it far outstripped them in its widespread application and indiscriminate brutality. Biological weapons were used against Chinese soldiers and civilians in several military campaigns.[45] In 1940, the Japanese Army Air Force bombed Ningbo with ceramic bombs full of fleas carrying the bubonic plague.[46] Many of these operations were ineffective due to inefficient delivery systems,[44] although up to 400,000 people may have died.[47] During the Zhejiang-Jiangxi Campaign in 1942, around 1,700 Japanese troops died out of a total 10,000 Japanese soldiers who fell ill with disease when their own biological weapons attack rebounded on their own forces.[48][49]
According to historians Benny Morris and Benjamin Kedar, Israel conducted a biological warfare operation codenamed "Cast Thy Bread" during the 1948 Arab–Israeli War. The Haganah initially used typhoid bacteria to contaminate water wells in newly-cleared Arab villages to prevent the population including militiamen from returning. Later, the biological warfare campaign expanded to include Jewish settlements that were in imminent danger of being captured by Arab troops and inhabited Arab towns not slated for capture. There was also plans to expand the biological warfare campaign into other Arab states including Egypt, Lebanon and Syria, but they were not carried out.[58]
International restrictions on biological warfare began with the 1925 Geneva Protocol, which prohibits the use but not the possession or development of biological and chemical weapons in international armed conflicts.[39][60] Upon ratification of the Geneva Protocol, several countries made reservations regarding its applicability and use in retaliation.[61] Due to these reservations, it was in practice a "no-first-use" agreement only.[62]
The 1972 Biological Weapons Convention (BWC) supplements the Geneva Protocol by prohibiting the development, production, acquisition, transfer, stockpiling and use of biological weapons.[6] Having entered into force on 26 March 1975, the BWC was the first multilateral disarmament treaty to ban the production of an entire category of weapons of mass destruction.[6] As of March 2021, 183 states have become party to the treaty.[63] The BWC is considered to have established a strong global norm against biological weapons,[64] which is reflected in the treaty's preamble, stating that the use of biological weapons would be "repugnant to the conscience of mankind".[65] The BWC's effectiveness has been limited due to insufficient institutional support and the absence of any formal verification regime to monitor compliance.[66]
In 1985, the Australia Group was established, a multilateral export control regime of 43 countries aiming to prevent the proliferation of chemical and biological weapons.[67]
Biological weapons are difficult to detect, economical and easy to use, making them appealing to terrorists. The cost of a biological weapon is estimated to be about 0.05 percent the cost of a conventional weapon in order to produce similar numbers of mass casualties per kilometer square.[69] Moreover, their production is very easy as common technology can be used to produce biological warfare agents, like that used in production of vaccines, foods, spray devices, beverages and antibiotics. A major factor in biological warfare that attracts terrorists is that they can easily escape before the government agencies or secret agencies have even started their investigation. This is because the potential organism has an incubation period of 3 to 7 days, after which the results begin to appear, thereby giving terrorists a lead.
A technique called Clustered, Regularly Interspaced, Short Palindromic Repeat (CRISPR-Cas9) is now so cheap and widely available that scientists fear that amateurs will start experimenting with them. In this technique, a DNA sequence is cut off and replaced with a new sequence, e.g. one that codes for a particular protein, with the intent of modifying an organism's traits. Concerns have emerged regarding do-it-yourself biology research organizations due to their associated risk that a rogue amateur DIY researcher could attempt to develop dangerous bioweapons using genome editing technology.[70]
In 2002, when CNN went through Al-Qaeda's (AQ's) experiments with crude poisons, they found out that AQ had begun planning ricin and cyanide attacks with the help of a loose association of terrorist cells.[71] The associates had infiltrated many countries like Turkey, Italy, Spain, France and others. In 2015, to combat the threat of bioterrorism, a National Blueprint for Biodefense was issued by the Blue-Ribbon Study Panel on Biodefense.[72] Also, 233 potential exposures of select biological agents outside of the primary barriers of the biocontainment in the US were described by the annual report of the Federal Select Agent Program.[73]
Though a verification system can reduce bioterrorism, an employee, or a lone terrorist having adequate knowledge of a bio-technology company's facilities, can cause potential danger by utilizing, without proper oversight and supervision, that company's resources. Moreover, it has been found that about 95% of accidents that have occurred due to low security have been done by employees or those who had a security clearance.[74]
Entomological warfare (EW) is a type of biological warfare that uses insects to attack the enemy. The concept has existed for centuries and research and development have continued into the modern era. EW has been used in battle by Japan and several other nations have developed and been accused of using an entomological warfare program. EW may employ insects in a direct attack or as vectors to deliver a biological agent, such as plague. Essentially, EW exists in three varieties. One type of EW involves infecting insects with a pathogen and then dispersing the insects over target areas.[75] The insects then act as a vector, infecting any person or animal they might bite. Another type of EW is a direct insect attack against crops; the insect may not be infected with any pathogen but instead represents a threat to agriculture. The final method uses uninfected insects, such as bees or wasps, to directly attack the enemy.[76]
Genetics
Theoretically, novel approaches in biotechnology, such as synthetic biology could be used in the future to design novel types of biological warfare agents.[77][78][79][80]
Would demonstrate how to render a vaccine ineffective;
Would confer resistance to therapeutically useful antibiotics or antiviral agents;
Would enhance the virulence of a pathogen or render a nonpathogen virulent;
Would increase the transmissibility of a pathogen;
Would alter the host range of a pathogen;
Would enable the evasion of diagnostic/detection tools;
Would enable the weaponization of a biological agent or toxin.
Most of the biosecurity concerns in synthetic biology are focused on the role of DNA synthesis and the risk of producing genetic material of lethal viruses (e.g. 1918 Spanish flu, polio) in the lab.[81][82][83] Recently, the CRISPR/Cas system has emerged as a promising technique for gene editing. It was hailed by The Washington Post as "the most important innovation in the synthetic biology space in nearly 30 years."[84] While other methods take months or years to edit gene sequences, CRISPR speeds that time up to weeks.[6] Due to its ease of use and accessibility, it has raised a number of ethical concerns, especially surrounding its use in the biohacking space.[84][85][86]
Ideal characteristics of a biological agent to be used as a weapon against humans are high infectivity, high virulence, non-availability of vaccines and availability of an effective and efficient delivery system. Stability of the weaponized agent (the ability of the agent to retain its infectivity and virulence after a prolonged period of storage) may also be desirable, particularly for military applications, and the ease of creating one is often considered. Control of the spread of the agent may be another desired characteristic.
The primary difficulty is not the production of the biological agent, as many biological agents used in weapons can be manufactured relatively quickly, cheaply and easily. Rather, it is the weaponization, storage, and delivery in an effective vehicle to a vulnerable target that pose significant problems.
For example, Bacillus anthracis is considered an effective agent for several reasons. First, it forms hardy spores, perfect for dispersal aerosols. Second, this organism is not considered transmissible from person to person, and thus rarely if ever causes secondary infections. A pulmonary anthrax infection starts with ordinary influenza-like symptoms and progresses to a lethal hemorrhagicmediastinitis within 3–7 days, with a fatality rate that is 90% or higher in untreated patients.[87] Finally, friendly personnel and civilians can be protected with suitable antibiotics.
The former US biological warfare program categorized its weaponized anti-personnel bio-agents as either Lethal Agents (Bacillus anthracis, Francisella tularensis, Botulinum toxin) or Incapacitating Agents (Brucella suis, Coxiella burnetii, Venezuelan equine encephalitis virus, Staphylococcal enterotoxin B).
The United States developed an anti-crop capability during the Cold War that used plant diseases (bioherbicides, or mycoherbicides) for destroying enemy agriculture. Biological weapons also target fisheries as well as water-based vegetation. It was believed that the destruction of enemy agriculture on a strategic scale could thwart Sino-Soviet aggression in a general war. Diseases such as wheat blast and rice blast were weaponized in aerial spray tanks and cluster bombs for delivery to enemy watersheds in agricultural regions to initiate epiphytotic (epidemics among plants). On the other hand, some sources report that these agents were stockpiled but never weaponized.[89] When the United States renounced its offensive biological warfare program in 1969 and 1970, the vast majority of its biological arsenal was composed of these plant diseases.[90] Enterotoxins and Mycotoxins were not affected by Nixon's order.
Though herbicides are chemicals, they are often grouped with biological warfare and chemical warfare because they may work in a similar manner as biotoxins or bioregulators. The Army Biological Laboratory tested each agent and the Army's Technical Escort Unit was responsible for the transport of all chemical, biological, radiological (nuclear) materials.
Biological warfare can also specifically target plants to destroy crops or defoliate vegetation. The United States and Britain discovered plant growth regulators (i.e., herbicides) during the Second World War, which were then used by the UK in the counterinsurgency operations of the Malayan Emergency. Inspired by the use in Malaysia, the US military effort in the Vietnam War included a mass dispersal of a variety of herbicides, famously Agent Orange, with the aim of destroying farmland and defoliating forests used as cover by the Viet Cong.[91] Sri Lanka deployed military defoliants in its prosecution of the Eelam War against Tamil insurgents.[92]
Anti-livestock
During World War I, German saboteurs used anthrax and glanders to sicken cavalry horses in U.S. and France, sheep in Romania, and livestock in Argentina intended for the Entente forces.[93] One of these German saboteurs was Anton Dilger. Also, Germany itself became a victim of similar attacks – horses bound for Germany were infected with Burkholderia by French operatives in Switzerland.[94]
During World War II, the U.S. and Canada secretly investigated the use of rinderpest, a highly lethal disease of cattle, as a bioweapon.[93][95]
In the 1980s Soviet Ministry of Agriculture had successfully developed variants of foot-and-mouth disease, and rinderpest against cows, African swine fever for pigs, and psittacosis to kill the chicken. These agents were prepared to spray them down from tanks attached to airplanes over hundreds of miles. The secret program was code-named "Ecology".[56]
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In 2010 at The Meeting of the States Parties to the Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and Their Destruction in Geneva[97]
the sanitary epidemiological reconnaissance was suggested as well-tested means for enhancing the monitoring of infections and parasitic agents, for the practical implementation of the International Health Regulations (2005). The aim was to prevent and minimize the consequences of natural outbreaks of dangerous infectious diseases as well as the threat of alleged use of biological weapons against BTWC States Parties.
Many countries require their active-duty military personnel to get vaccinated for certain diseases that may potentially be used as a bioweapon such as anthrax, smallpox, and various other vaccines depending on the Area of Operations of the individual military units and commands.[98][99]
Public health and disease surveillance
It is important to note that most classical and modern biological weapons' pathogens can be obtained from a plant or an animal which is naturally infected.[100]
In the largest biological weapons accident known—the anthrax outbreak in Sverdlovsk (now Yekaterinburg) in the Soviet Union in 1979—sheep became ill with anthrax as far as 200 kilometers from the release point of the organism from a military facility in the southeastern portion of the city and still off-limits to visitors today, (see Sverdlovsk Anthrax leak).[101]
Thus, a robust surveillance system involving human clinicians and veterinarians may identify a bioweapons attack early in the course of an epidemic, permitting the prophylaxis of disease in the vast majority of people (and/or animals) exposed but not yet ill.[102]
For example, in the case of anthrax, it is likely that by 24–36 hours after an attack, some small percentage of individuals (those with the compromised immune system or who had received a large dose of the organism due to proximity to the release point) will become ill with classical symptoms and signs (including a virtually unique chest X-ray finding, often recognized by public health officials if they receive timely reports).[103] The incubation period for humans is estimated to be about 11.8 days to 12.1 days. This suggested period is the first model that is independently consistent with data from the largest known human outbreak. These projections refine previous estimates of the distribution of early-onset cases after a release and support a recommended 60-day course of prophylactic antibiotic treatment for individuals exposed to low doses of anthrax.[104] By making these data available to local public health officials in real time, most models of anthrax epidemics indicate that more than 80% of an exposed population can receive antibiotic treatment before becoming symptomatic, and thus avoid the moderately high mortality of the disease.[103]
Single cause of a certain disease caused by an uncommon agent, with lack of an epidemiological explanation.
Unusual, rare, genetically engineered strain of an agent.
High morbidity and mortality rates in regards to patients with the same or similar symptoms.
Unusual presentation of the disease.
Unusual geographic or seasonal distribution.
Stable endemic disease, but with an unexplained increase in relevance.
Rare transmission (aerosols, food, water).
No illness presented in people who were/are not exposed to "common ventilation systems (have separate closed ventilation systems) when illness is seen in persons in close proximity who have a common ventilation system."
Different and unexplained diseases coexisting in the same patient without any other explanation.
Rare illness that affects a large, disparate population (respiratory disease might suggest the pathogen or agent was inhaled).
Illness is unusual for a certain population or age-group in which it takes presence.
Unusual trends of death and/or illness in animal populations, previous to or accompanying illness in humans.
Many affected reaching out for treatment at the same time.
Similar genetic makeup of agents in affected individuals.
Simultaneous collections of similar illness in non-contiguous areas, domestic, or foreign.
An abundance of cases of unexplained diseases and deaths.
Bioweapon identification
The goal of biodefense is to integrate the sustained efforts of the national and homeland security, medical, public health, intelligence, diplomatic, and law enforcement communities. Health care providers and public health officers are among the first lines of defense. In some countries private, local, and provincial (state) capabilities are being augmented by and coordinated with federal assets, to provide layered defenses against biological weapon attacks. During the first Gulf War the United Nations activated a biological and chemical response team, Task Force Scorpio, to respond to any potential use of weapons of mass destruction on civilians.
The traditional approach toward protecting agriculture, food, and water: focusing on the natural or unintentional introduction of a disease is being strengthened by focused efforts to address current and anticipated future biological weapons threats that may be deliberate, multiple, and repetitive.
The growing threat of biowarfare agents and bioterrorism has led to the development of specific field tools that perform on-the-spot analysis and identification of encountered suspect materials. One such technology, being developed by researchers from the Lawrence Livermore National Laboratory (LLNL), employs a "sandwich immunoassay", in which fluorescent dye-labeled antibodies aimed at specific pathogens are attached to silver and gold nanowires.[106]
In the Netherlands, the company TNO has designed Bioaerosol Single Particle Recognition eQuipment (BiosparQ). This system would be implemented into the national response plan for bioweapon attacks in the Netherlands.[107]
Researchers at Ben Gurion University in Israel are developing a different device called the BioPen, essentially a "Lab-in-a-Pen", which can detect known biological agents in under 20 minutes using an adaptation of the ELISA, a similar widely employed immunological technique, that in this case incorporates fiber optics.[108]
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