Look at the casualty figures from any war before the late 19th century (and many since) and you’ll find something quite startling; disease killed many times more soldiers than actual combat did. When the Spanish besieged Granada in 1489 they lost 3,000 men to the Moors but 17,000 to typhus. In 1527 another typhus epidemic saved the Spanish garrison of Naples when of the 35,000 French soldiers surrounding them, 25,000 died in a single month. This was seen as divine intervention and led to Charles I of Spain becoming Charles V of the Holy Roman Empire in 1530. In this role he tried to subdue the Protestant Germans of Metz, but God seems to have changed sides and Charles was forced to retreat as typhus killed 10,000 of his troops. Further epidemics drove the Austrians out of Hungary in 1560 (30,000 dead,) scattered Maximillian II’s army in 1568, killed millions during the first half of the Thirty Years War from 1618-1648, let the French into Prague in 1741 by eliminating 30,000 of its Prussian defenders, crushed Napoleon’s Grand Armée on its way to Moscow and killed as many as 300,000 of them (and 219,000 when he tried again the next year) and wiped out a quarter of the Serbian army in November 1914 (200,000 dead.) As late as 1945 a hint of typhus was enough to scatter armies in panic.
For any military historian this is an appalling list of carnage. It’s only the beginning, though. That’s only a few selected incidents picked from one study, and it’s only typhus. Plague killed millions more during the second half of the Thirty Years War, and that was only a minor outbreak by plague standards; in 1348 it brought the Hundred Years War to a stop for eight years after 45 percent of the European population – and a much higher proportion of the troops, who lived close together in insanitary camps – died. Tiny bands of Spanish conquistadores defeated huge Central American empires as smallpox, influenza, measles and diphtheria ripped through their opponents. Many of Napoleon’s 300,000 disease casualties in 1812 may have died of dysentery instead of – or as well as – typhus. The quickest route to promotion in the 18th century British Army (if you survived) was a posting to the West Indies, where yellow fever decimated the ranks and reduced battalions to companies in a year. In the American Civil War 250,000 US and 164,000 Confederate soldiers died of disease, 69 percent and 63 percent of the respective total deaths. For centuries disease slaughtered the participants in every war.
Not surprisingly, this got people thinking.
The first recorded attempt to use biological weapons came early; the Hittites drove tularaemia victims into the lands of their enemies in around 1,200 BCE, causing an epidemic. Athens was poisoning wells with toxic plants by 590 BCE and Hannibal had clay pots of venomous snakes hurled onto enemy ships. The survivors of the Black Death catapulted the corpses of plague victims into enemy towns and the British gave smallpox-infected blankets to hostile Native American tribes during Pontiac’s Rebellion. Biological warfare has a long history and despite treaties banning it it’s still a threat.
So what is biological warfare? It’s the use of a biological substance as a weapon. These substances can be a toxin – like botulinum – or an infectious agent such as a bacteria or virus, or even possibly an insect or other pest. Many can be passed from one victim to another, although not all can. There are many ways to attack with a biological agent; some can be delivered in shells or aircraft sprays like a chemical weapon, others by releasing infected rodents or insects. They can be used in conventional warfare or terrorism, and may be targeted against an enemy’s population, livestock or crops. They have the potential to cause devastation on a global scale and they’re not hard to make.
Modern biological warfare research started just before the Second World War; the Japanese attempted to use typhoid against the Soviet Army by infecting a river, then attacked Chinese towns with ceramic bombs containing plague-infected fleas. Up to 400,000 Chinese died from Japanese biological weapons. In response to this and to (inaccurate) fears that Germany was also developing bioweapons the USA, UK and Canada started a programme of their own. By the time this was finished tularaemia, anthrax, brucellosis and botulinum had been weaponized and Gruinard Island, off the Scottish coast, had been bombed with anthrax and left uninhabitable. In 1948 the Red Cross reported that Haganah terrorists had contaminated the water supply of Acre with bacteria and caused a typhoid epidemic; another group apparently tried to do the same in Gaza, but were captured and shot by Egyptian soldiers. During the Cold War research accelerated. The UK abandoned biological weapons early on but the USA and USSR created large programmes. Both sides weaponized a large number of agents and developed delivery systems. In 1968 the USAF accidentally sprayed a large flock of sheep in Utah with something they said was VX nerve agent but probably wasn’t; over 6,000 died. In April 1979 something nasty escaped from a Biopreparat weapons plant near the Soviet city of Sverdlovsk and 105 people died of anthrax. There are persistent allegations that both sides used bioweapons in conflicts including Korea, Vietnam and Afghanistan. Among the agents created was a Soviet hybrid of Ebola and smallpox, which is potentially what epidemiologists call a “slate wiper.”
President Nixon stopped US bioweapon research in 1969; in 1972 the UK proposed the Biological Weapons Convention, which bans the production of all biological and toxin weapons. Only sixteen countries have refused to sign the convention and of these only Israel has the capacity to develop sophisticated weapons. However several countries are currently believed to have offensive bioweapon programmes: China, Cuba, Egypt, Iran, Israel, North Korea, Russia, Syria and Taiwan.
Biological weapons have problems. Infectious agents can spread uncontrollably, and may turn on their users. This risk can be reduced by the use of vaccines or suitable antibiotics, but there is still a risk of them getting out of control. Other organisms, like anthrax, don’t spread easily between victims but the mess can be very hard to decontaminate afterwards. To make Gruinard Island safe for sheep again took 48 years and two major decontamination efforts; in the end the entire island had to be sprayed with formaldehyde. On the other hand many agents are very vulnerable to the environment. Anthrax obviously isn’t, but the Ebola virus is easily destroyed by sunlight and the bacteria that produces botulinum dies rapidly in air.
Defence against a biological attack can be done in a number of ways. For military forces standard chemical, biological, radiological and nuclear (CBRN) protective equipment, such as suits and respirators, gives a high degree of protection. Tablet kits such as the Biological Agent Pre-treatment Set can reduce vulnerability to many agents and mass vaccination of troops was carried out before the Persian Gulf wars. Vaccines can slow or stop the spread of infectious agents in civilian populations, and even high standards of hygiene can have a big impact. Any health system capable of dealing with natural epidemics is also effective against infectious biological agents. There are antidotes to many toxins (although not all – in 1978 the Bulgarian secret police shot and killed Georgi Markov with a ricin-filled pellet in London.) Unless a genetically engineered or mutant organism is released modern medicine can greatly reduce the effects of a biological attack.
There’s one effect that’s very hard to reduce though – fear. Potentially the greatest power of bioweapons is the terror they can create. It’s unlikely that any state would dare openly use one, because they’re classed as weapons of mass destruction and that would invite a nuclear response. For a non-state group which aims to spread fear and chaos, though, bioterrorism is a very attractive option. So far terrorist efforts have been small and had limited success, but you can bet they’re working on it.