Bioweapons: When diseases become a weapon

Biological Weapons: When Diseases Become Weapons Published October 19, 2026 Last updated October 20, 2026Artificial intelligence could in the future also be misused for the development of biological weapons. This sounds like science fiction, but it is currently occupying the minds of scientists, security agencies, and international organizations. This is because advances in biotechnology allow for even more precise analysis and modification of pathogens. AI can process large amounts of data more quickly. Experts therefore point out that modern technologies could also be misused for the development of biological weapons in the long term. Security agencies are also observing this development with concern. Ken McCallum, the head of the British domestic intelligence service MI5, warned in October 2026 that artificial intelligence could increase the danger from existing or even new biological weapons in the future—even in the hands of so-called non-state actors. Biological Weapons: A Tightrope Walk Between Science and Abuse As is the current debate, a report by the US AI company Anthropic from September 2026 shows this. According to the company, several attempts were detected and blocked in which researchers wanted to use the AI Claude in connection with potential biological weapons research. According to the report, this included grant applications for so-called Gain-of-Function research and projects to investigate avian flu variants that might be more easily transmissible to mammals. Anthropic also emphasized that such research can serve both medical precautions and military purposes. This difficult separation between legitimate science and possible abuse is considered one of the biggest problems in controlling modern biotechnologies. What are Biological Weapons? However, the fear of biological weapons is by no means new. Numerous pathogens are in question as biological means, including bacteria, viruses, fungi, or certain biological toxins. Known examples are anthrax, plague, smallpox, or botulinum toxin. Anthrax is considered one of the most well-known biological weapons. The resistant spores can persist in the environment for a long time and have also been investigated in state biological weapons programs. The World Health Organization (WHO) and the United Nations (UN, Office for Disarmament Affairs) define biological weapons as the deliberate release of such biological substances to harm humans, animals, or plants. A biological weapon generally includes two components: the biological agent itself and a system to spread it. Experts speak of an "agent," such as viruses or bacteria, and a "delivery mechanism." This includes, among others, rockets, spray systems, or contaminated food. Biological weapons belong to the group of so-called ABC weapons together with nuclear weapons and chemical weapons. They are often also counted among weapons of mass destruction. How do they differ from chemical weapons? The difference between biological weapons and chemical weapons lies in their mode of action. Chemical weapons harm humans through the toxic effect of chemical substances, such as sarin or tear gas. The effect occurs often within seconds or minutes. Examples include the nerve gas attacks with chlorine gas and later tear gas in World War I or the use of the nerve agent sarin in the Syrian civil war. Biological weapons, on the other hand, cause infectious diseases. Their effect can only occur after hours, days, or weeks. Some pathogens can also spread from person to person, which makes their consequences difficult to predict. Simply put, chemical weapons act through their immediate toxicity, while biological weapons cause diseases. The possible spread from person to person makes biological weapons particularly difficult to calculate. Are Biological Weapons banned worldwide? Yes, biological weapons are internationally prohibited. The Biological Weapons Convention (BWC) entered into force in 1975. It prohibits the development, production, storage, transfer, and use of biological and toxin-based weapons. The convention can be seen as a further development of the Geneva Protocol of 1925, which only prohibited the use of biological weapons as a method of warfare. 189 states are parties to this agreement. Some countries like Egypt, Syria, or Israel have not ratified or signed the treaty. Those who have ratified the convention also commit to destroying all stockpiles, production facilities, and means of transport. Chemical weapons are also internationally prohibited. However, their control is considered much more developed. The Chemical Weapons Convention is monitored by the Organisation for the Prohibition of Chemical Weapons (OPCW). This body can conduct inspections and control the destruction of chemical weapons stockpiles. There is no comparable control system for biological weapons to date. States fear that inspections could reveal sensitive research data from medicine, the pharmaceutical industry, or biotechnology. Therefore, the control of biological weapons is largely based on transparency, voluntary reporting, and international trust. The fact that a ban alone is not enough to stop use is shown by one of the most well-known examples that occurred in the USA in 2001: A few weeks after the September 11th attacks, letters containing anthrax spores were sent. 22 people were infected, five died. Why are Biological Weapons so difficult to detect and control? Detecting biological weapons programs is significantly more difficult than controlling nuclear or chemical weapons. Many technologies that can be used for the development of biological weapons also have civilian applications. The same laboratory equipment used in the development of vaccines or medicines could theoretically also be used for military research. Experts speak of a "dual-use" problem: research can serve peaceful, medical, and military purposes simultaneously. In addition, a biological attack can initially look like a natural disease outbreak. Whether a pathogen was intentionally released or arose naturally can often only be determined after extensive investigations. Perhaps this is why biological weapons have been used repeatedly in history. Historical accounts include poisoned wells to the use of the bodies of plague victims during sieges. However, the actual effectiveness of such methods is controversial.