What are Biological Weapons?
The most important question at the beginning of any discussion on biological weapons is what exactly is meant by a biological weapon?
Key biological agents validated for biological weapons in past programmes
Bacillus anthracis
Anthrax is an acute infectious disease caused by Bacillus anthracis. It was the first disease for which a microbial origin was established — by Robert Koch in 1876.
Inhalation anthrax, the deadliest form, initially presents with flu-like symptoms such as a sore throat, fever, muscle aches, and malaise. A brief improvement is typically followed by respiratory failure and shock, often accompanied by meningitis.
Bacillus anthracis is one of the most feared biological warfare agents. It is easily disseminated, can cause high mortality rates, and poses a significant public health threat. Additionally, it may lead to widespread panic and social disruption, necessitating extensive preparedness measures.
Yersinia pestis
Plague, one of the oldest recorded diseases, is caused by the bacterium Yersinia pestis.
There are two primary forms: classic bubonic plague and pneumonic plague. The latter, which involves inhalation of the bacterium, has historically been a target in bioweapons programs.
Pneumonic plague presents with symptoms including malaise, high fever, chills, headache, and muscle pain. This progresses to septicaemic shock, respiratory failure, and often death.
Yersinia pestis is a strong candidate for biological weapons due to its ease of culture, mass production potential, and aerosolization capabilities.
Variola major
Smallpox, caused by the variola virus, is a highly contagious viral disease that was officially eradicated in 1980.
It manifests as fever, severe headaches, and a rash of small, solid, raised lesions. These lesions later fill with fluid, becoming inflamed and pus-filled, typically causing extreme pain.
Variola major is considered a potent biological weapon due to its hardy nature, high infectiousness via airborne transmission, ability to survive explosive delivery, and its capacity to cause a debilitating disease with high mortality.
Francisella tularensis
Tularemia, caused by the bacterium Francisella tularensis, primarily affects small mammals.
In humans, pneumonic tularemia presents with fever, headaches, chills, cough, chest pain, and difficulty breathing. Skin lesions and swollen lymph nodes may also develop, and the disease can be fatal.
Francisella tularensis is dangerous due to its ability to be aerosolized, causing large-scale tularemia outbreaks in both humans and animals. It is a resilient bacterium, highly infectious, and capable of surviving in various environments, including water, moist soil, hay, straw, and decaying carcasses.
Brucella
Brucella bacteria infect humans primarily through ingestion of contaminated milk or meat or through contact with broken skin.
Brucellosis, more common in animals like pigs, sheep, cattle, and dogs, causes flu-like symptoms in humans, including fever, headache, chills, and malaise. In some cases, nausea, vomiting, and diarrhea develop. Rarely, the infection may affect the heart and nervous system.
Brucella is regarded mainly as an incapacitant or as an anti-animal weapon intended to disrupt agricultural production.
Venezuelan equine encephalitis (VEE) virus
In natural settings, the Venezuelan equine encephalitis (VEE) virus exists in a rodent-mosquito cycle and only sporadically causes human infections. Mutations enabling replication in horses can lead to widespread equine outbreaks, killing thousands of horses and spreading across vast distances.
In humans, the severity of VEE infections varies significantly. Some strains cause high mortality and permanent neurological damage.
The virus is highly infectious and grows well in laboratory conditions, but advances in medicine have revealed that it is less controllable than previously believed when it served as a biological agent in the US.
Biological weapons are usually placed in the same category as chemical and nuclear weapons, in other words, weapons of mass destruction. There are, however, some overlaps and things get blurry.
Relationship between BTW and other non-conventional weapons
Source: Grübelfabrik,CC BY-NC-ND 4.0
The overlap between biological and chemical weapons is most evident in the realm of toxins and bioactive molecules, as these substances can be derived from both biological organisms and synthetic chemical processes. Toxins such as botulinum and ricin are naturally occurring biological agents that can be weaponized, blurring the line between biological and chemical warfare. However, these agents are covered by the prohibitions contained in both the Biological Weapons Convention and the Chemical Weapons Convention. Additionally, advances in biotechnology may enable the synthesis and enhancement of bioactive molecules, which can be used to disrupt physiological functions in a manner similar to some traditional chemical weapons.