As early as 184 B. C. (Before Christ), biological agents have been used as wartime weapons and by terrorist groups. In ancient times, well before the discovery of bacteria and the study of microbiology, living organisms such as snakes and fleas were used to harm and to spread disease.
In modern times, scientists process biological agents and chemicals in laboratories for research purposes. Unfortunately, potential terrorists may gain access to them through purchase or theft. The threat of an individual or group intentionally infecting crops, livestock, or other parts of the food chain still exists today.
Since ancient times, biological and chemical agents have been used during warfare to defeat the enemy. In recent times, they have been used not only to harm individuals during war, but also to terrorize society. While humans are often the focus of such attacks, agricultural resources have also been a military target since World War 1(1914-1918). To gain a better understanding of the public health context and potential impact of agroterrorism, it is helpful to review the history of agroterrorism events, devastating agricultural disease outbreaks, incidents of widespread food contamination, and other related historical events.
The following timeline from Emory University, a world-class research institution located in Atlanta, Georgia, USA highlights some of the events significant to the history of agroterrorism.
ANCIENT TIMES In ancient times, crude forms of biological and chemical weapons were used during war to defeat the enemy.
Chemicals were used as early as 1000 B.C., when the Chinese warriors blew arsenical smoke toward their enemies to incapacitate them.
In 600 B.C., Solon of Athens poisoned the drinking water of Kirrha, a village in Phocis, central Greece, with hellebore roots. The Black Hellebore, once known as Melampode, is a perennial, low-growing plant with dark, shining, smooth leaves and flower-stalks rising directly from the root. Its pure white blossoms appear in the depth of winter and thus, it was named “Christmas Rose.” The generic name of this plant is derived from the Greek word elein (to injure) and bora (food), and indicates its poisonous nature.
In 200 B.C., the Carthaginians (Phoenicians) poisoned their own wine with Mandrake root and left it behind as they retreated from their enemy. Knowing their enemy would drink the wine the Carthaginians attacked the enemy once the Mandrake roots took effect and sedated the warriors.
19TH-EARLY 20TH CENTURY
Cattle Plague/Rinderpest During the 19th century and early 20th century, devastating outbreaks of cattle plague (also known as rinderpest) occurred throughout Europe, Africa, the United States, and even in the Philippines (1887-1939). Cattle plague is a contagious disease that affects livestock, including cows, sheep, goats, camels, pigs, and other wild animals.
Legislation was passed to enable slaughter, livestock movement controls, and import restrictions, which eventually eliminated the disease. These actions became the foundation of current eradication policies.
Fortunately, the 19th century outbreak has been the only outbreak of cattle plague in the United States. Cattle plague is still a problem in parts of East Africa and the Indian subcontinent.
“The Jungle” In 1905, author Upton Sinclair published a book titled The Jungle which exposed the brutalization and exploitation of workers in a Chicago meatpacking house. The Jungle describes the filthy conditions in these houses and how this posed a threat to meat consumers. Sinclair urged President Theodore Roosevelt to support federal inspection of meatpacking houses. The following year, both the Food and Drug Act and the Meat Inspection Act were passed.
German Germ Warfare
Between 1915 and 1918, the discovery of germs and their disease-causing capabilities was well established. Germans infected livestock with glanders and anthrax (biological agents that affect both livestock and people) that were bound for the United States, Europe, and South America. Even if there are conflicting reports of how successful the program was at causing disease in the recipient countries, the act was well documented scientifically.
FMD Outbreak Foot and Mouth Disease (FMD) is a disease which infects cloven foot animals, such as cattle and pigs, and was first recorded in Great Britain in 1839. The highly contagious, acute viral disease is rarely fatal, yet it causes long term reduction in livestock productivity, resulting in economic loss. Humans can be briefly infected and become carriers of the disease, but illness has only been rarely reported.
The 1839 outbreak drew attention to the lack of veterinary knowledge on farm livestock, and the inexistence of a government authority to handle the disease. In the late 19th century and early 20th century, Great Britain experienced several devastating FMD outbreaks. As a result, livestock diseases became a course of veterinary study and the British government established the first permanent FMD Research Station in 1924.
The rinderpest (or cattle plague) outbreak in Europe led to the creation of the Office International des Epizooties (OIE) in 1924. This intergovernmental organization was created on January 25, 1924 by 28 countries. Today, the organization has approximately 167 member countries.
Its mission is to ensure global transparency of animal diseases; to collect, analyze and disseminate veterinary scientific information; to provide expertise and encourage international solidarity in the control of animal diseases; to improve the legal framework and resources of national veterinary services; and to safeguard world trade by publishing health standards for animals and animal products.
Geneva Protocol The proliferation of chemical and biological weapons during World War I led to the development of the Geneva Protocol which prohibits the use of biological and chemical agents during warfare. Developed at the 1925 Geneva Conference for the Supervision of the International Traffic in Arms, the Geneva Protocol restated the prohibition previously established in the Treaty of Versailles and the Washington Treaty, which banned the use of poisonous gases.
The Protocol added a ban on bacteriological warfare such as poisoning drinking water or infecting the food supply during war. The signed document did not prevent countries from producing biological agents or conducting research.
Before World War II, all of the great powers ratified the Protocol except Japan and the United States. Eventually, it was ratified by President Gerald R. Ford in 1975.
WORLD WAR II (1939-1945)
Between 1937 and 1945, Canada, Great Britain, Japan, the United States, and the USSR studied many animal and plant diseases for offensive and defensive purposes. Animal diseases included anthrax, brucellosis, glanders, rinderpest, Newcastle disease, and fowl plague. Crop diseases included late blight of potato, rice blast, brown spot of rice, rubber leaf blight, southern blight, and wheat rust.
In addition, the Japanese allegedly used anthrax and rinderpest against Russia and Mongolia. Britain also accused Germany of dropping cartons of Colorado potato beetles in Southern England during the War.
Brucellosis Outbreak Brucellosis is a zoonotic disease that was fairly common in humans, cattle, swine, and goats prior to the 20th century. In the 1940s, the US began an eradication program to eliminate brucellosis from livestock. Today, most states are brucellosis-free, but there are continuous efforts to eliminate the disease from wildlife and the livestock in contact with them.
The six-year history of brucellosis eradication efforts in the U.S. highlights how difficult it is to eliminate a disease once it is native to an animal population. The ease of aerosol spread of this disease made it a choice for bioterrorism, and the U.S. developed and tested bombs containing brucella organisms in field tests in the 1940s. This program was discontinued by 1967. Natural human infection in the U.S. decreased dramatically, following the nationwide establishment of milk pasteurization laws in 1949. Today, only 100-200 cases are reported each year, and many of these are associated with foreign exposures.
Brucellosis is a complex disease with many strains that continue to emerge and remains a major source of illness in human and domesticated animals worldwide.
1950s AND 1960s
Food Industry Revolutionized After World War II, the food industry began to change and intensify. The industry became increasingly consolidated and expanded its distribution channels, in part due to the advent of mechanical refrigeration units. The changes that began in the 1950s greatly increased the vulnerability of the food supply, and created a system that could be catastrophically affected by widespread contamination. Further compounding this vulnerability was the fact that food inspectors generally looked for visible contamination, rather than for underlying disease agents.
COLD WAR (1970s) During the tense time of the Cold War, the United States and Russia built strong biological weapons programs.
1942-1969 U.S. Tests The United States Army began an offensive biological weapons program by converting Camp Detrick (now Fort Detrick) in Frederick, Maryland into a facility for research and development. The research program included testing many zoonotic animal diseases including anthrax, botulism, plague, tularemia, Q fever, Venezuelan equine encephalitis virus, and brucellosis. They also produced 5,000 anthrax bombs.
Nixon Nixes In 1969, President Richard M. Nixon put an end to the offensive biological weapons program by signing an executive order terminating offensive biological weapons production, (including animal and plant diseases) in the United States and ordering all stockpiles of weapons be destroyed. The biological weapons program was converted to a defensive program, with biological agents used strictly for research purposes.
Agent Orange Agent Orange and “Super Orange” were the nicknames given to an herbicide and defoliant used by the U.S. military in Herbicidal Warfare program during the Vietnam War. Agent Orange was used from 1961 to 1971, and was by far the most used of the so-called “rainbow herbicides” utilized during the program Degradation of Agent Orange - as well as Agents Purple, Pink and Green - released dioxins, which have caused harm, to the health of those exposed during the Vietnam War. Agents Blue and White were part of the same-program but did not contain dioxins.
Studies of populations highly exposed to dioxin, though not necessarily Agent Orange, indicate increased risk of various types of cancer and genetic defects: the effect of long-term low-level exposure, however, has not been established.
Weapons Convention The 1972 Biological and Toxin Weapons Convention banned the possession of biological agents except for defensive research and thus, became the first world treaty banning an entire class of weapons, including weapons for agroterrorism. The United States and 102 other countries signed the treaty; however, there was no clear method to enforce.
Soviet Slip In 1979, an outbreak of anthrax in the city of Sverdlovsk (now called Ekaterinburg) killed nearly 70 people. The Soviet government claimed the outbreak was due to the improper handling of food by black marketers who had allowed meat contaminated with anthrax to be distributed in the region, and that the anthrax was transmitted through meat consumption. International scientific intelligence communities were skeptical and later their . skepticism would be validated.
LATE 20TH CENTURY Bioterrorism During the late 20th century, the potential for bioterrorism in the United States increased, with Iraq and Middle Eastern terrorist groups as potential instigators. Through intelligence reports, it was learned that Iraq’s biological weapons program had included research into the offensive use of zoonotic diseases such as anthrax, botulinum toxins, and aflatoxins, among other agents. At the end of the Gulf War in 1991, the United Nations Special Commission found SCUD missiles in Iraq loaded with biological agents. While tensions increased in the Middle East, other instances of bioterrorism occurred around the world.
Bird Flu Between 1983 and 1984 there was an avian influenza epidemic in the United States which caused the death and destruction of 13 million birds. Avian influenza, also known as “bird flu,” is a highly contagious viral disease affecting mainly chickens, turkeys, ducks and other birds.
Infection causes a wide spectrum of symptoms, ranging from mild illness to a highly contagious and rapidly fatal disease known as “highly pathogenic avian influenza”. Under certain circumstances avian influenza can pose a serious threat to humans, although this disease should not be confused with human influenza, a common disease.
The first documented case of human infected with avian influenza virus occurred in Hong Kong in 1997. The outbreak caused severe respiratory disease in 18 people, six of whom died. The human infection coincided with an epidemic of avian influenza in Hong Kong’s poultry population.
Like many other animal infectious diseases, avian influenza is easily transmitted from farm to farm through contaminated equipment, vehicles, feed, cages, or clothing. The diseasecausing viruses can survive for long periods in the environment, especially when temperatures are low. Standard control measures include quarantining of infected farms and destruction of infected or potentially exposed flocks.
Today, avian influenza is a serious threat to human health. Efforts to contain the disease in Asian poultry have not been successful, and bird flu outbreaks are continuing in Thailand and Vietnam. According to World Health Organization (WHO), human contact with infected birds has resulted in at least 319 illnesses, 192 of which were fatal.
The WHO has warned that avian influenza may become the next influenza pandemic - an epidemic that occurs over a large geographic area and affects a large portion of the population - in human populations. The high mortality in birds and humans associated with the virus makes it very devastating if used as an agent of agroterrorism.
BSE Bovine spongiform encephalopathy (BSE), a degenerative neurological disease which targets cattle, was first recognized in the United Kingdom in 1986. BSE is also known as “mad cow disease” because of its symptoms. There is still no treatment for the disease.
Humans cannot contract BSE through direct contact with infected cattle. However, humans can develop variant Creutzfeldt-Jakob disease, a form of the BSE, by consuming brain matter from an infected animal. In the past, some composite meat products, such as hotdogs, have included brain matter. Due to the threat of BSE, the practice of including brain and nervous system material in composites has been discontinued.
The discovery of BSE in United Kingdom cattle led countries around the world to ban imports of British beef. These,bans caused serious economic consequences for the British beef industry.
Cattle Plague Vaccine In 1999, Dr. Walter Plowright was awarded the World Food Prize for developing a vaccine against rinderpest. Dr: Plowright is a veterinary scientist who devoted his career to the eradication of the cattle plague. From 1956 to 1970, the cell-culture vaccine and its widespread application to field use were developed at the Muguga Laboratory of the East African Veterinary Research Organization that was led by Dr. Plowright. The Food and Agriculture Organization (FAO) of the United Nations predicts that with vaccination, cattle plague will be eradicated by 2010.
“Biohazard” In 1999, the best-selling book Biohazard, written by Dr. Ken Alibek and Stephen Handelman, was released. Between 1988 and 1992, Dr. Alibek was chief scientist and the first deputy chief of Bioprepart, the Soviet pharmaceutical agency responsible for the Soviet biological weapons program. Biohazard discusses the details of one of the most covert operations of the Cold War. The book describes the 20year production of biological weapons in the former Soviet Union, including tons of anthrax, plague and smallpox.
Widespread Food Recalls The widespread food recalls that resulted from outbreaks of foodborne disease in the late 20′ century is of a major relevance to the history of agroterrorism. Although the introduction of these agents in the food chain was not intentional, the resulting outbreaks and economic impacts speak of the possible damage.
In 1993, an outbreak of E. coli 0157″H7 in ground beef occurred in the Pacific Northwest, which caused 700 illnesses and four deaths. Doctors at a hospital in Seattle, Washington noticed that an unusual number of children were being admitted with bloody diarrhea. The cause was foodborne illness that was traced to undercooked hamburgers, contaminated with E. coli, from a local Jack in the Box restaurant. Jack in the Box issued an immediate recall of the contaminated ground beef. The Jack in the Box chain almost went out of business due to the bad publicity.
A similar outbreak in Colorado in 1997 resulted in one of the largest food recalls in U.S. history, in which over 25 million pounds of hamburger were recalled and a beef processing plant in Nebraska was temporarily shut down.
As a result of these outbreaks, food inspection became more stringent and several states passed legislation requiring restaurants to serve thoroughly cooked hamburgers.