The Deadly Scourge That Terrorized Humanity
Imagine a disease so terrifying that it killed roughly one in three people it touched, leaving survivors permanently scarred and often blind. Smallpox had a mortality rate of about 30%, killing at least 1 in 3 people infected, making it one of history’s most feared killers. Throughout the 18th century, variola major was responsible for around 400,000 deaths annually in Europe alone. For centuries, this viral nightmare stalked human civilization, leaving death and disfigurement in its wake across every continent.
The disease didn’t discriminate between rich and poor, young and old. During the 18th century, the disease killed an estimated 400,000 Europeans each year, including five reigning monarchs, and was responsible for a third of all blindness. The symptoms were as gruesome as they were deadly, beginning with fever and progressing to fluid-filled lesions covering the entire body, often leading to death within just two weeks.
Two Faces of the Same Monster
Variola major had a fatality rate of around 30%, while variola minor’s mortality rate was about 1%, showing how the same virus could manifest in dramatically different ways. The more dangerous variola major dominated most of the world, while the milder variola minor appeared mainly in certain regions. The ordinary form is the most common (~90 percent) with a 30 percent case fatality rate, but there were even deadlier variants lurking in the shadows.
The flat form accounts for about 5 percent of cases, and has a 97 percent case fatality rate. The hemorrhagic form accounts for less than 3 percent of cases but has a 100 percent fatality rate. These extreme forms meant that even when people thought they understood smallpox, the virus could still surprise them with its lethality. Children were particularly vulnerable, with mortality rates climbing even higher among the youngest victims.
A Trail of Destruction Across Civilizations
The earliest evidence of the disease dates to around 1500 BCE in Egyptian mummies, showing that smallpox has been humanity’s companion for millennia. Ancient records from multiple civilizations document its devastating impact, with the earliest written description of a disease like smallpox appeared in China in the 4th century CE (Common Era). Early written descriptions also appeared in India in the 7th century and in Asia Minor in the 10th century. The virus seemed to follow human trade routes and exploration, spreading wherever people traveled.
Galen’s description of the Antonine Plague, which swept through the Roman Empire in 165–180 CE, indicates that it was probably caused by smallpox… It raged for fifteen years and greatly weakened the Roman empire, killing up to one-third of the population in some areas. Total deaths have been estimated at 5 million. This ancient pandemic helped bring down one of history’s greatest empires, showing how a microscopic virus could topple civilizations.
The New World Catastrophe
When European explorers brought smallpox to the Americas, the results were nothing short of apocalyptic. Within a few years smallpox claimed between 60% and 90% of the Inca population, with other waves of European disease weakening them further. Indigenous populations had no immunity to this foreign plague, making the conquest of vast empires possible through biological warfare, whether intentional or not.
The devastation wasn’t limited to South America. After reading Tomison’s journals, Houston and Houston calculated that, of the Indians who traded at the Hudson and Cumberland houses, 95% died of smallpox. Paul Hackett adds to the mortality numbers suggesting that perhaps up to one-half to three-quarters of the Ojibway situated west of the Grand Portage died from the disease. The Cree also suffered a casualty rate of approximately 75% with similar effects found in the Lowland Cree. Entire tribes were wiped out, forever altering the demographic landscape of North America.
The Twentieth Century’s Deadliest Secret
Even as medicine advanced, smallpox continued its relentless march through the 1900s. One of history’s deadliest diseases, smallpox is estimated to have killed more than 300 million people since 1900 alone. Until it was completely eradicated from the Earth in the late 1970s, it is estimated that smallpox killed at least 300,000 people worldwide during the first three-quarters of the 20th century. Most experts placed the number of deaths due to smallpox around a half a billion during its last 100 years (approximately 1877 to 1977).
These staggering numbers reveal how smallpox remained humanity’s most persistent enemy well into the modern era. During the 20th century, it is estimated that smallpox was responsible for 250–500 million deaths, making it possibly the single deadliest disease in human history. The virus continued to terrorize populations even as other medical advances were saving lives from different causes.
Before Jenner: The Dangerous Dance with Death
Long before Edward Jenner’s breakthrough, people were desperate enough to try a risky procedure called variolation. First, variolation was used, a dangerous procedure that consists in inoculating intradermally a small quantity of virus from convalescent patients. This practice involved deliberately infecting people with live smallpox material, hoping they would develop a milder case and survive with immunity. It was medical Russian roulette, but the alternative – waiting for natural infection – seemed worse.
In 1717, Lady Montagu learned of the practice called inoculation to prevent smallpox, which used blister material from a mild case of smallpox. It had long been known that a small number of smallpox cases were much milder with a much lower incidence of death (1% to 5%), subsequently known as variola minor, as opposed to typical, severe smallpox (variola major). The procedure spread from the Ottoman Empire to Europe, offering the first glimmer of hope against the disease, despite its inherent dangers.
The Milkmaid’s Secret That Changed Everything
In the countryside of 18th-century England, farmers had noticed something remarkable about their milkmaids. Milkmaids, who were renowned for their clear complexions, were often immune to smallpox and its scarring pock marks. Their work brought them into contact with cowpox, a mild disease of cattle that only left a single pustule on the hands of people who milked the cows. This folk knowledge would become the key to humanity’s greatest medical triumph.
The record shows that it was there that Jenner heard a dairymaid say, “I shall never have smallpox for I have had cowpox. I shall never have an ugly pockmarked face.” It fact, it was a common belief that dairymaids were in some way protected from smallpox. While others might have dismissed this as superstition, Edward Jenner saw the potential for a medical revolution. The connection between cowpox and smallpox protection would prove to be one of the most important observations in medical history.
May 14, 1796: The Day That Changed Medicine Forever
On a spring day in 1796, Edward Jenner made medical history with a simple but groundbreaking experiment. In May 1796, Edward Jenner found a young dairymaid, Sarah Nelms, who had fresh cowpox lesions on her hands and arms… On May 14, 1796, using matter from Nelms’ lesions, he inoculated an 8-year-old boy, James Phipps. This wasn’t just another medical procedure – it was the birth of vaccination as we know it.
Phipps reacted to the cowpox matter and felt unwell for several days but made a full recovery. Two months later, in July 1796, Jenner took matter from a human smallpox sore and inoculated Phipps with it to test his resistance. Phipps remained in perfect health, the first person to be vaccinated against smallpox. The boy’s survival after deliberate smallpox exposure proved that cowpox could provide protection, launching the age of immunization.
From Rejection to Recognition
In 1797, Jenner sent a short communication to the Royal Society describing his experiment and observations. However, the paper was rejected. The medical establishment wasn’t ready for such a radical idea. Undeterred, Jenner continued his work and gathered more evidence. Then in 1798, having added a few more cases to his initial experiment, Jenner privately published a small booklet entitled An Inquiry into the Causes and Effects of the Variolae Vaccinae.
The technique of introducing material under the skin to produce protection against disease became universally known as vaccination, a word derived from the Latin name for the cow (vacca), in Jenner’s honour. What started as a rejected paper became the foundation for modern immunology. Jenner’s persistence in the face of skepticism showed how revolutionary ideas often face resistance before gaining acceptance.
The Long Road to Global Eradication Begins
Despite Jenner’s breakthrough, it would take nearly two centuries to completely eliminate smallpox. While some European regions eliminated the disease by 1900, smallpox was still ravaging continents and areas under colonial rule, with over 2 million people dying every year. It took another 50 years to achieve global solidarity in the fight against the disease. The vaccine had to reach every corner of the world, a logistical challenge that seemed almost impossible.
In 1958 Professor Viktor Zhdanov, Deputy Minister of Health for the USSR, called on the World Health Assembly to undertake a global initiative to eradicate smallpox. The proposal (Resolution WHA11.54) was accepted in 1959. At this point, 2 million people were dying from smallpox every year. The initial campaign struggled with limited resources and competing priorities, showing how difficult it would be to coordinate a worldwide effort.
1967: The Intensified Campaign That Saved the World
In 1959, the World Health Organization (WHO) started a plan to rid the world of smallpox. Unfortunately, this global eradication campaign suffered from a lack of funds, personnel, and commitment from countries, and a shortage of vaccine donations. Despite their best efforts, smallpox was still widespread in 1966, causing regular outbreaks across South America, Africa, and Asia. The Intensified Eradication Program began in 1967 with a promise of renewed efforts.
The Global Smallpox Eradication Program was launched by WHO. During the first year of the program, 44 countries, 31 of which had endemic smallpox, reported 217,218 cases. The renewed campaign brought together unprecedented international cooperation, with the United States and Soviet Union working together despite the Cold War. Advanced freeze-dried vaccines and innovative delivery methods like the bifurcated needle made mass vaccination campaigns more effective than ever before.
The Final Victory: October 26, 1977
The last naturally occurring case of indigenous smallpox (Variola minor) was diagnosed in Ali Maow Maalin, a hospital cook in Merca, Somalia, on 26 October 1977. The last naturally occurring case of the more deadly Variola major had been detected in October 1975 in a three-year-old Bangladeshi girl, Rahima Banu. After centuries of terror, smallpox was finally cornered to a single case in the Horn of Africa.
Thanks to the combined efforts of national health agencies, WHO and scientists around the world, smallpox was eliminated from South America in 1971, Asia in 1975 and Africa in 1977. The cost of the Intensified Smallpox Eradication Programme was approximately US$300 million, two thirds of which came from endemic countries for their own eradication efforts. The investment was minimal compared to the lives saved and the economic burden lifted from affected nations.
The Legacy: Humanity’s Greatest Medical Triumph
Smallpox was declared officially eradicated by the World Health Assembly in 1980, and there have been no naturally occurring cases since then. Smallpox is the first and only infectious disease that has been eradicated in humans, which means it no longer exists naturally anywhere in the world. This achievement represents humanity’s greatest victory over disease, proving that global cooperation and scientific innovation could conquer even the most ancient plagues.
The most feared disease of all time had been eradicated, fulfilling a prediction that Edward Jenner had made in 1801. It has been estimated that the task he started has led to the saving of more human lives than the work of any other person. Today, children grow up in a world free from the terror of smallpox, thanks to centuries of human determination and the courage of pioneers like Jenner who dared to challenge death itself.
From ancient Egyptian mummies to modern laboratory freezers, smallpox traced a path of destruction through human history that spanned over three millennia. The disease that once toppled empires and terrorized continents now exists only in two secure facilities, a testament to what humanity can achieve when science and global cooperation unite against a common enemy. The victory over smallpox didn’t just save millions of lives – it showed the world that no disease, no matter how ancient or deadly, is beyond our reach.