Incidents where biological substances have been used offensively are relatively rare. In most cases, suspected attacks turn out to be hoaxes or accidental incidents. However, historically there have been a number of examples of weaponisation and application of biological substances. Below is a list of selected historical examples to illustrate the span of incidents:
| Year | Geography | Responsible | Agent | Goal and application | Effect |
|---|---|---|---|---|---|
| 1763 | Fort Pitt (today Pittsburg in the USA) | British army | Smallpox | Attack on Indians using contaminated blankets | Possibly an outbreak of smallpox among native Americans(1) |
| 1914-1918 | USA, Argentina, Romania, Norway, Spain | Germany | Anthrax, Glanders | Horses and mules being shipped to the Entente Powers were infected with anthrax or glanders | Unknown numbers of dead horses and mules(2) |
| 1928-1992 | Soviet Union | Communist regime | Anthrax, Smallpox, Marburg, Plague, Typhoid | Offensive biological programme | Several accidents, including: Aralsk (1971)(3), Sverdlovsk (1979)(4) |
| 1937-1945 | China | Japan | Plague, Anthrax, Cholera, Typhoid | Brutal human experiments on civilians. Contamination of water supply and airstrikes on cities | Hundreds of thousands died or became severely ill(5) |
| 1940-1944 | Poland, Germany | Polish home army ZWZ-AK | Typhoid, Anthrax, Dysentery, Glanders, Rabies, Cholera, Botulism, Staphylococcus aureus | Primary German troops, Nazi, SS and Gestapo, but also German civilians | According to Polish sources several thousand cases of deaths and severe illness. German numbers are much lower(6) |
| 1941-1944 | Soviet Union (Ukraine and Belarus) | Soviet partisans and special forces | Typhoid and Aconitine | Primary German occupation troops and Soviet collaborators | At least 100 died in Slavuta in Ukraine in 1942(7) |
| 1975-1980 | Rhodesia | Government forces | Cholera, Botulinum toxin, anthrax | Eliminate communist insurgency movement | 171,990 cattle and 17,199 human cases of anthrax infection. 200 humans died from anthrax(8) |
| 1981-93 | South Africa | The South African Apartheid regime | Anthrax, Plague, Cholera, Botulinum toxin, Ricin | Anthrax was used for individual assassinations, and cholerae for contaminating water supplies in Namibia | Unknown number of fatalities and cases of illness among people(9) |
| 1985-91 | Iraq | Saddam Hussein’s dictatorship | Anthrax, Botulinum toxin, Ricin, Aflatoxin, Perfrigens toxin | Offensive programme | No known cases were such weapons were used(11) |
| 1984 | Dalles, OR, USA | Religious sect | Salmonella | Food contamination (salad bars) | 751 persons food poisoned(10) |
| 1990-1995 | Tokyo | Aum Shinrikyo | Anthrax (Non-pathogenic strain), Botulinum | Aerosol dissemination in Tokyo | No reported fatalities and probably no cases of illness(12) |
| 1996 | Dallas , TX, USA | Shigella | Food contamination (doughnuts) | 12 food poisoned(13) | |
| 2001 | USA | Anthrax | Anthrax letters sent to news agencies and senators via US Postal Service | 22 cases of illness and 5 deaths(14) | |
| 2018 | Germany | Islamic State | Ricin | Attempt to build cluster bomb to disseminate ricin | German police arrested the terrorists(15). According to German sources, the bomb could have killed more than 100 people(16) |
| 2019 | Tunisia | Islamic State? | Anthrax | Letters send to journalists, activists and politicians | The letters were intercepted before they reached their intended victims(17) |
| 2019 | China | Criminal gangs | African swine fever virus | Drones were used to drop pork products contaminated with the virus on pig farms | Unknown, but presumably the attacks worsened an already existing outbreak of the virus in Chinese pig farms(18) |
| 2024 | Belgium | Unknown | Brucine | Letters send to government buildings | The letters were intercepted before they reached their intended victims (19) |
