“From ancient times right up to the 21st Century, militaries either in garrison or on campaign have had to do battle with disease.”
THE ANCIENT GREEK city-state of Athens was in a fight to the death against Sparta in 430 BCE when a new and even deadlier foe entered the field.
Without warning that summer, Athenian soldiers, sailors and citizens began to fall ill. Within days, hundreds had succumbed. Soon the death toll was in the thousands. The unknown yet highly infections plague was likely carried to the city by way of a trading vessel sailing in from North Africa. Eventually, the outbreak wiped out 30,000 citizens. It would soon spread across the wider Greek world, decimating the populations of other city states too.
The ancient historian Thucydides, who was himself infected, reported that the illness produced a high fever, coughs, an unquenchable thirst, delirium, running sores, convulsions, diarrhea and, in most cases, death. Those who got better, were often robbed of their sight; others lost their memories. While historians today dispute whether this killer virus was typhoid, ebola, or even the bubonic plague, its clear that the epidemic shattered the Athenian army and navy and killed an estimated one-third of the city’s population.  Among its victims was the military leader Pericles. His loss proved to be a serious blow to Athens’ war effort. The outbreak also led to a general collapse of law and order in the city. Residents blamed the gods for the scourge and many swore off religion. Others gave into wine and debauchery.
While the disease hobbled Athens’ defences, the Spartans who were already marching on the city, called off their campaign for fear of coming in contact with the contagion themselves. Spared a siege, Athens would limp forward, the Peloponnesian War (as it would become known) would rage for another 25 years and ultimately spell the end of the golden age of Athens.
This plague was one of the first recorded epidemics to ravage an army, but it wouldn’t be the last. Here are some others to consider.
Typhus: 1 – Napoleon: 0
It wasn’t enemy musket balls or cannon shot that destroyed Napoleon’s army that invaded Russia in 1812, nor was it the brutally cold winter. It was fleas and lice – more specifically a disease spread by their bite: typhus. In fact, the outbreak was already silently hollowing out the core of Bonaparte’s half-million-man army even before the first French soldier set foot on Russian soil. However, once the invasion was under way, the disease, which is characterized by severe headaches, debilitating fatigue, high fever, and body aches, would end up killing more of Bonaparte’s troops than the Russians could ever hope to.
As the infected French army marched ever-deeper into Russia, as many as 6,000 soldiers were falling ill daily. Bonaparte’s surgeons were baffled by the epidemic, entirely unaware that disease-laden parasites were spreading unchecked as the soldiers huddled together each night in cramped tents and bivouacs.
Eyewitnesses recorded that along the invasion routes into the heart of Russia, scores of French soldiers simply dropped to the side of the road to die. By the fall, with up to two thirds of his army either dead or sick, Napoleon put Moscow to the torch and ordered a general withdrawal from Russia.
The illness along with the approaching winter claimed nearly all of Napoleon’s retreating legions. The cost of the the epidemic was staggering — the French Emperor marched into Russia in June with 600,000 troops, by November he had fewer than 50,000.  The entire episode left Bonaparte greatly weakened and exposed. Within a year and a half, Paris would fall to a coalition of France’s enemies and Napoleon’s Empire was no more.
Scurvy at Sea
While not a communicable disease, scurvy was still notorious for wiping out entire ships’ companies during long sea voyages throughout history. The disease, which is caused by a deficiency of vitamin C, is characterized by fatigue, depression, painful spots on the skin, and gum decay. If left unchecked, scurvy leads to open sores, loss of teeth, fever, jaundice and eventually death. Although the condition is most commonly associated with sea travel during the 15th through 18th centuries, the ancient Greek physician Hippocrates described the malady as early as 400 BC. 
Ironically, the cure for scurvy was widely known for centuries, the world’s navies were slow to adopt this knowledge. A household cookbook written in 1707 by an English woman named Ebot Mitchell prescribes orange juice as a known curative while a Scottish physician named James Lind published a book on preventing scurvy in 1753 using lime juice. Sadly for ships’ crews, attempts at introducing the treatment proved ineffective – lime that’s boiled or concentrated in copper kettles loses its vitamin C, as does juice that’s been exposed to air. Other ‘experts’ wrongly figured that not just citric acid, but any acid would ward off scurvy.  As a result, sailors would continue to die of scurvy in large numbers for decades to come. During the Seven Years War alone, of the 185,000 sailors conscripted or pressed, 133,000 perished from the disease before the end of the conflict – again more than would ever die in battle.  Scurvy continued to weaken the navy through the American Revolution.
It wasn’t until the 1790s and the health reforms of the British surgeon Gilbert Blane that fresh citrus fruit was made widely available on His Majesty’s ships. This most often came in the form of mandatory lime rations. By the time of the Napoleonic Wars, the British navy was largely free of scurvy, although outbreaks would continue to strike expeditions to remote parts of the planet when food supplies would dwindle. Not surprisingly, the French military also battled scurvy throughout the 18th and early 19th Century. Napoleon’s favourite surgeon, Dominique-Jean Larrey noted during the campaign in Egypt that soldiers who ate horse meat (which is also rich in vitamin C) seemed immune from scurvy.  As a result the consumption of meat from horses became common in 19th Century France.
Malaria: The Constant Enemy
Armies throughout history have fallen prey to malaria, a mosquito-borne infection that causes fever, coma and sometimes death. In fact, one leading contemporary expert on the disease, Dr. B.S. Kakkilaya of Mangalore, India, says that much of military history is little more than a study in the effects of the malaria. From ancient times right up to the 21st Century, militaries either in garrison or on campaign have had to do battle with this lethal malady. Here are just a few armies and military leaders felled by malaria.
One of history’s most celebrated commanders, Alexander the Great, likely died of malaria.  Historians suspect that the 33-year-old conqueror contracted the malady at the very climax of his epic march from Macedon, through Egypt, Persia and into western India.
The disease would affect not just Greek but Roman history as well. No fewer than three would-be-conquerors of Rome fell victim to malaria.  Attila the Hun’s army was decimated by it as they marched on the failing Roman Empire. The army of Barbarossa (aka Frederick I) suffered a similar fate. So did the forces of Byzantine general Belisarius as he sough to besiege the city in 536 AD. Even Alaric, the Gothic ruler who sacked Rome in 410 AD was struck dead by malaria in the days following his triumph.
Centuries later, malaria would ravage the ranks of the British army as it fought to suppress the American Revolution. Entire regiments fell victim, particularly those operating in the southern colonies. In fact, some suggest that malaria helped weaken the red coats’ defence of Yorktown, helping to make an American victory there possible.  Recognizing the danger the disease posed to its army, the Continental Congress began the War of Independence by spending $300 (a sizeable sum in 1775) to procure quinine, a medicine used to prevent malaria.
In 1809, a British force sent to fight the French in the soggy, mosquito-infested Low Countries was ground to a halt by malaria – out of the 39,000 troops that landed Walcheren, more than a quarter fell ill. 
Fifty years later, as many as 1.3 million combatants succumbed to the disease during the American Civil War, with supposedly half of soldiers in the conflict falling ill annually. 
Troops fighting in Europe, the Middle East and the tropics in both world wars would also have to contend with the disease. Malaria continues to dog armies in the field to this day, particularly those in Afghanistan and Iraq.
Smallpox, a lethal virus that produces fatigue, fever and diarrhea along with painful disfiguring blisters on the hands, feet, face and body, has ravaged human populations for thousands of years. In fact, archeologists have found evidence of epidemics as far back as Ancient Egypt. And for centuries after the pharaohs, smallpox would tear through empires and kingdoms across Europe, Asia and Africa claiming millions of lives. Amazingly, pre-Columbian American natives had virtually zero exposure to the disease — that is until germ-carrying Europeans arrived in the New World in the late 15th and early 16th centuries.
Hernan Cortez was among the first to unleash smallpox on the people of the New World, albeit unknowingly. When the notorious conquistador’s vastly-outnumbered army was forced to quit its mission to conquer Mexico in 1519, the invaders unwittingly left behind a surprise for the Aztecs: the body of a Spaniard killed in battle that just happened to be infected. Finding an entire population with no immunity, the germ quickly spread through the city of Tenochtitlan and within two years virtually the entire Aztec army was dead along with more than a quarter of the population.  Upon their return, Cortez’s men reported not being able to walk through the streets of the captital because of the piles of dead left unburied.  For the next two centuries, the disease would spread like wildfire throughout native populations across the New World, carried overland through inter-tribal contact, or delivered into communities via European traders, missionaries and explorers. As many as 90 to 95 percent of all native inhabitants of the Americas would eventually die from the disease. 
(Originally published on Aug. 29, 2012)
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