List Of Lethal Biological Weapons
List Of Lethal Biological Weapons

List Of Lethal Biological Weapons

What are “Bioweapons” or “Biological Weapons” ?

Bioweapons also known as Biological Weapons. The microorganisms (organisms which cannot be seen with naked eyes) like Bacteria, Fungi, Virus, Toxins or other Substances that are produced or released to cause disease or death in humans, animals or plants. The use of Bioweapons are serious problem. These Bioweapons are so lethal that it can cause mass destruction.

The dissemination or intentional release of these microorganisms to cause harm to humans or animals are called as “Bioterrorism”. The main use of bioweapons is to threaten people, governments and countries. Terrorists always use such agents because of the following reasons:

  1. They are extremely difficult to detect
  2. Some of the agents can easily spread from person to person
  3. They are inexpensive
  4. Effective in very minute amount (micro-litre)
  5. Can cause widespread fear and panic beyond the actual physical damage
  6. Easily disseminated

The use of bioweapon in an act of war is called as “Biological Warfare” or “Germ Warfare”. There is a recorded history of using biological toxins and agents as a weapons of war in World war I and II.

These agents are typically found in nature, where they are not harmful. But later they are mutated or altered to increase their ability to cause disease. Many agents are altered in such way to make them resistant to medicines, or to increase their ability to be spread into the environment.

The list of 15 Lethal Biological Weapons of history are as follows :

[1] Anthrax

  • Name of Infection : Anthrax
  • Causative Agent : Bacteria – Bacillus anthracis
  • Infectious to : Humans and animals

Bacillus anthracis, the name have been derived from the Greek word “anthrakis” which means “coal” as it causes black coal like skin lesions. Human anthrax naturally occurs in three clinical forms:

  1. Cutaneous Anthrax : When spores come in contact with the skin and develops black lesions.
  2. Gastrointestinal Anthrax : This occurs by the consumption of infected animal products and undercooked or raw meat.
  3. Respiratory Anthrax : Caused by the inhalation of spores through respiration.

Out of which Gastrointestinal Anthrax is the most fatal. All the three forms can lead to septicemia and death if untreated.

  • During World War I (1917 and 1918) There is evidence that the German army used anthrax to secretly infect livestock and animal feed traded to the Allied Nations.
  • Great Britain also experimented with anthrax on a small island called Gruinard Island. They release bombs containing anthrax over the island, where 80 sheep have been placed. All of the sheep died from anthrax.
  • Japan used anthrax as a weapon and conducted research in Japanese-occupied Manchuria. During the experiment, prisoners have been infected with anthrax. Japanese attacked at least 11 Chinese cities with anthrax and other biological agents by spraying them directly onto homes from aircraft.
  • The United States conducted experiments with anthrax at Mississippi and Utah. Where more than 5,000 bombs have filled with anthrax in response to any possible attacks from Germany.

Reasons to use Bacillus anthracis as biological agent:

  1. Anthrax spores easily found in nature, and can be produced in a laboratory.
  2. The spores can last for a long time in the environment. The spores can survive up to 40 years in water or soil.
  3. Released quietly in the nature without anyone knowing. The microscopic spores put into powders, sprays, food, and water.
  4. They are so small, that no one can able to see, smell, or taste them.
  5. The spores remain resistance to harsh environmental conditions like heat and humidity, disinfectants and UV radiation.
Microscopic image of Bacillus anthracis
Microscopic image of Bacillus anthracis

[2] Plague

  • Name of Infection : Plague
  • Causative Agent : Bacteria – Yersinia pestis
  • Infectious to : Humans, Rodents and Fleas

Plague is an infectious disease caused by a naturally occurring bacterium Yersinia pestis, found primarily in wild rodents. It is one of the most serious bioterrorism threats. The oldest account of plague have been mentioned in the First Book of Samuel, in Bible.

There are three forms of naturally occurring plague :

  1. Pneumonic plague : It occurs due to the inhalation of aerosols containing bacteria and it affects the lungs.
  2. Bubonic plague : Acquired through the bite of an infected flea. It generally affects lymph nodes.
  3. Septicemic plague : It occurs as a result of untreated bubonic or pneumonic plague.
  • First pandemic of plague

The first plague incident of bubonic plague called as the “Great Plague of Justinian”. The disease originated in Egypt in 532 AD and spread through the Middle East regions.

  • Second pandemic of plague

Known as “Black Death or Great Pestilence“, appeared in 1334 in China and spread to India, Venice and Europe.

Due to second pandemic of plague more than one third of European population were killed, that is around 20 to 30 Million people.

  • Third pandemic of plague

In 1930 more than 26 million cases and 12 million deaths have been reported.

In early 20th century, 10,000 fatal cases of contagious pneumonic plague have reported in Manchurian epidemics.

Microscopic image of Yersinia pestis
Microscopic image of Yersinia pestis

[3] Small Pox

  • Name of Infection : Small pox
  • Causative Agent : Virus – Variola virus
  • Infectious to : Humans
  • Transmitted through : Nose and mouth secretions
  • Mortality Rate : 30-50%

Smallpox affects people of all ages but has the highest mortality rates among the young and the elderly people. There are three phases of clinical smallpox infection:

  1. Incubation : It lasts between 7 and 14 days
  2. Prodrome period : Characterized by a high fever with some other symptoms including malaise, headache, and backache.
  3. Pox : At this stage, small red lesions appear on tongue and palate.
  4. Telltale rash : The rash appears in the form of macule and papule ,which then turn into scabs and gradually fall off leaving unpigmented marks. Indivduals are contagious until all of the scabs have fallen off.
  • In early 14th century, Tartar forces to put the corpses of smallpox victims into the towns to weaken and destroy entrapped defenders.
  • Smallpox also used as a biological weapon by commander of Fort pitt during the French and Indian Wars (1754–1767). Soldiers distributed blankets used by smallpox patients with the intention of starting an outbreaks among American Indians. And these epidemic killed more than 50% of infected tribes.

World Health Organization (WHO) started a worldwide vaccination program for small pox. In 1980 WHO officially declared that the disease is successfully eradicate.

Edward Jenner developed the smallpox vaccine, the world’s first vaccine. The terms vaccine and vaccination are derived from Variolae vaccinae, the term devised by Jenner to denote cowpox

[4] Cholera

  • Name of Infection : Cholera
  • Causative Agent : Bacteria – Vibrio cholerae
  • Infectious to : Humans
  • Accquired By : Drinking or eating contaminated water and food

Cholera can cause life-threatening thin, grayish brown, mucoid diarrhoea. Other symptoms includes intense vomiting and leg cramps. Victims lose 10-12 liters of fluids a day. The Centre for Disease Control (CDC) estimates that “2.9 million cases and 95,000 deaths” occur globally each year. V. cholerae toxins is the primary causes of cholera’s lethal symptoms.

  • The disease was first emerged in the Calcutta, India in 1800s. Since then, the world has faced 7 cholera pandemics.
  • The First Asiatic Cholera Pandemic :

The first pandemic have suspected in Kumbh festival and lasted from 1817 to 1823. Around 10,000 British troops and countless Indians died during this pandemic. By 1820, the pandemic had spread to Thailand, Indonesia, Russia and Turkey.

  • The Second Pandemic :

Immigrants brought the deadly pandemic to Canada and the United States in 1832, and it spread down to Mexico and Cuba. The pandemic reached to Portugal, Spain, France, Italy and Syria at the end of 1833.

  • The Third Pandemic :

It begins in India from 1846 to 1863. It was the most deadly pandemic of the cholera. The pandemic began in the lower Bengal region and spread to Afghanistan and other conturies.

Morphology of Vibrio cholerae

[5] Tularaemia as potential bioweapon

  • Name of Infection : Tularaemia
  • Causative Agent : BacteriaFrancisella tularensis
  • Infectious to : Humans and Animals
  • Transmitted through : Bites of infected arthropods, Handling infectious animals, Tissues or Fluids, Direct contact or ingestion of contaminated water, food or soil and Inhalation of infective aerosols

Tularaemia is a dangerous potential biological weapons as it is easily dissemination and it has extreme pathogenic abilities. F. tularensis have two subspecies:

(1) F. tularensis biovar tularensis (type A), and

(2) F. tularensis biovar palaearctica (type B)

  • United States and Japan studied that during World War II, F. tularensis was used as a biological weapon.
  • Tularaemia, one of severe biological weapon used by the U.S. military in the late 1960s.
Transmission of Tularemia to Human by Ticks and the Life Cycle of Francisella tularensis in Nature

[6] Botulism

  • Name of Infection : Botulism
  • Name of Toxin : Botulinum
  • Causative Agent : Bacteria – Clostridium botulinum
  • Infectious to : Humans
  • Accquired By : Ingestion of raw, inadequately heated or unheated vacuum-packed foods.
  • Toxicity Level : 50–100 times

Botulinum toxins pose a major threat as biological weapons because they are extremely potent and lethal. Botulinum being neurotoxins causes serious paralytic illness. C. botulinum produces 8 types of toxin (A,B,C…., H) the most potent toxins known.

There are 3 types of naturally occurring botulism :

  1. Foodborne botulism : Caused by ingestion of food or drink containing botulinum toxin.
  2. Wound botulism : Accquired when C. botulinum multiples and produce botulinum toxin in the deep and contaminated anaerobic wound, and then absorbed into the bloodstream.
  3. Intestinal botulism : Result of eating food contaminated with C. botulinum spores that produces botulinum toxin in the intestine.
  • These toxin have used by Japanese during World War II. In the 1990s, the Japanese cult attempted to launch several terror attacks with BoNT, but all of them failed.
  • The United States produced botulinum toxin during WWII, and designated it as “Agent X.”
Microscopic image of spore forming Clostridium botulinum

[7] Ebola Virus Disease (EVD)

  • Name of Infection : Ebola Virus Disease (EVD) or Ebola Hemorrhagic Fever (EHF)
  • Causative Agent : Virus – Ebola Virus
  • Infectious to : Humans and Non-Human Primates like Monkeys, Gorillas and Chimpanzees
  • Mortality Rate : 25-90%
  • Transmitted through : Direct contact with the blood, body fluids and tissues of animals. Virus gets into the body through broken skin or mucous membranes of eyes, nose or mouth. People can get the virus through sexual contact with someone who has EVD.

Ebola virus was first discovered in 1976 near the Ebola River. Since then, the virus has been infecting people from time to time, leading to outbreaks in several African countries. Signs and symptoms of EVD are fever, mascular pain, headaches, rash, vomiting, sore throat and Diarrhoea. Some people begin to bleed both internally and externally.

  • EVD was first appeared in 1976 in African remote villages.
  • The Ebola Hemorrhagic Fever outbreak in 2014, it is the biggest in history with almost 9000 cases and 53% of fatality rate.

[8] Shigellosis

  • Name of Infection : Shigellosis
  • Causative Agent : Bacteria – Shigella
  • Infectious to : Humans and Primates like Monkeys
  • Acquried by : Consuming contaminated food or water

Shigella infection can cause diarrhoea (sometimes bloody), fever and stomach cramps. Washing your hands often with soap and running water and taking other hygiene measures can give protection against infection. There are several different kinds of Shigella bacteria: S. dysenteriae (group A), S. flexneri (group B), S. boydii (group C), and S. sonnei (group D).

  • During World War II, the Japanese biological weapons program Unit 731 in Manchuria experimented with shigellosis on prisoners of war.
  • In 2005, about 140 million people worldwide infected with shigellosis and 600,000 people died from the disease.
  • In 1997, a laboratory worker stole samples of Shigella bacteria and contaminated muffins and doughnuts. His co-workers suffered shigellosis from eating contaminated snacks. The attacked caused cases of gastroenteritis.

[9] Marburg Virus

  • Infection : Hemorrhagic fever
  • Causative Agent : Virus – Marburg Virus
  • Infectious to : Humans and Non-Human Primates
  • Fatality Rate : Upto 80%
  • Transmitted by : Exposure to one species of fruit bats or transmitted between people via body fluids through unprotected sex and broken skin.

In 1960s there is a small outbreak of Marburg virus disease in the German cities because the German workers were exposed to tissues of infected grivet monkeys at industrial plant. During these outbreaks, 31 people became infected and seven of them died.

The Soviet Union had an extensive offensive and defensive Bioweapons program that focused on the study of Marburg virus (MARV), Ebola virus (EBOV) and Lassa virus (LASV) as the pathogenicity of these viruses are very high and it is comparatively lethal.

Marburg virus pathogenesis

[10] Lassa Virus

  • Name of Infection : Lassa Fever or Lassa Hemorrhagic Fever (LHF)
  • Causative Agent : Virus – Lassa Virus
  • Infectious to : Humans and Primates
  • Transmitted through : Contact with materials contaminated with rodent urine or feces. LFV can transmit from person-to-person.

The virus affects organs such as the liver, spleen and kidneys. Disease may include gastrointestinal involvement with nausea, vomiting, diarrhoea and constipation. Other complications include bleeding, edema and conjunctivitis.

It is endemic in West African countries, especially the Republic of Guinea, Nigeria, and Liberia. Around 300,000 to 500,000 cases of LVF have been reported annually with 5,000 death cases.

[11] Nipah Virus

  • Name of Infection : Nipah Virus Infection
  • Causative Agent : Virus – Nipah henipavirus
  • Infectious to : Humans and animals
  • Transmitted through : Bats and infected animals
  • Mortality Rate : 40-60%

Symptoms in humans includes Encephalitis and Respiratory related problems.

The first case of Nipah virus infection as biological weapons is identified in 1998, during a large outbreak of viral encephalitis in Malasiya. The outbreak caused the highly virulent virus to be introduced into pig farms by fruit bats. From pigs the virus is easily transmitted to humans who came into close contact with infected pigs or other animal. This outbreak resulted in the death of around one million pigs.

Transmission of biological weapons NiV

[12] COVID-19

  • Name of Infection : COVID-19
  • Causative Agent : Corona Virus (SARS-CoV-2) strain
  • Infectious to : Humans
  • Transmitted through : Droplets of saliva or discharge from the nose when an infected person coughs or sneezes
  • Mortality Rate : Upto 100%

On 31 December 2019, WHO reported a case of pneumonia of unknown cause in Wuhan City, China. 7 January 2020 a novel coronavirus have identified and named as the “2019-nCoV”. On 11 March 2020, the rapid increase in the number of cases outside China led the WHO Director-General to announce that the outbreak could be characterized as a pandemic. By then around 17 Million cases were reported in India with 200k deaths and worldwide around 147 Million cases were reported with 3.1 Million deaths.

Coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus.It can cause mild to severe respiratory illness. Older peoples are highly susceptible because of their weak immune system. Peoples with underlying medical problems like cardiovascular disease, Asthama, diabetes, chronic respiratory disease and cancer are more likely to develop serious illness.

The best way to prevent and slow down transmission is to be well informed about the COVID-19 virus, the disease it causes and how it spreads. Protect yourself and others from infection by washing your hands or using an alcohol based rub frequently and not touching your face.

[13] Aflatoxin

  • Name of Toxin : Aflatoxin
  • Toxin Producing Agent : Molds – Aspergillus flavus and Aspergillus parasiticus
  • Infectious to : Humans and Animals

The term “Aflatoxin” have derived from the name of one of the molds that produce it, Aspergillus flavus. Aflatoxins are poisonous carcinogens and mutagens. Children are more affected by aflatoxin exposure, which can cause stunted growth, delayed development, liver damage and liver cancer. Adults have a higher tolerance to exposure, but are also at risk.

The mold that produce the toxins are found on plants like rice, peanuts, millet, sunflower seeds, sesame seeds, wheat, cottonseed, wheat etc. When contaminated food is processed, aflatoxins enter the food supplies.

  • There is a history of using Aflatoxins as a bio weapon agent by Iraq.
  • In 2003, 120 death cases reported due to acute poisoning in Kenya.
  • 2019, five brands of wheat flour have banned due to contamination of Aflatoxin in Kenya.
  • 2021, contamination of pet food caused death of 70 dogs in USA.S
Source of Aflatoxin

[14] Rinderpest

  • Name of Infection : Rinderpest or Cattle plague
  • Causative Agent : Virus – Rinderpest Virus (RPV)
  • Infectious to : Clovenhoofed animals like Cattle and Buffalo
  • Transmitted through : Direct contact, Drinking contaminated water, and could also be transmitted by air
  • Mortality Rate : Upto 90%

In developing countries rinderpest was responsible for famines and devastating economic losses. The symptoms includes fever, oral erosions, diarrhoea, lymphoid necrosis.

  • The first case of Rinderpest is reported in Central Europe, spreading later to Middle East, Europe, Africa and Asia.
  • Africa faced devastating famines due to outbreaks of Rinderpest.
  • Rinderpest also considered as a biological weapon in the United Kingdom’s program during World War II.

After a global eradication campaign since the mid-20th century, the last confirmed case of rinderpest was diagnosed in 2001.

[15] Rice blast

  • Name of Infection : Rice blast
  • Causative Agent : Fungi – Magnaporthe grisea
  • Infectious to : Rice plant

Rice being a staple food in Asia, around 90% of the rice is harvest in Asia. In the Philippines, due to Rice blast rice yield losses range from 50% to 85%. Rice blast is a devastating disease and annually worldwide faces loss of $66 million.

Blast symptoms can occur on leaves, leaf collars, nodes and panicles. The most serious damage occurs when the fungus attacks nodes just below the head. The stems often break at the diseased node. The stage of the disease is referred to as “rotten neck.”

Symptoms of Rice blast disease

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