History of Smallpox Vaccination

One of the deadliest diseases known to humans, smallpox remains the only human disease to have been eradicated. Many believe this achievement to be the most significant milestone in global public health.

Over thousands of years, smallpox killed hundreds of millions of people. The rich, the poor, the young, the old. It was a disease that didn’t discriminate, killing at least 1 in 3 people infected, often more in the most severe forms of disease.

The symptoms of smallpox were gruesome: high fever, vomiting and mouth sores, followed by fluid-filled lesions on the whole body. Death would come suddenly, often within 2 weeks, and survivors could be left with permanent harms such as blindness and infertility. 

Smallpox was highly infectious, with no known cure. It began as early as 1350 BCE, with cases being found in the study of Egyptian mummies.

This consisted of transferring to healthy people small amounts of material from smallpox sores, resulting in milder forms of illness and much lower mortality than natural infection. Some sources suggest practices of variolation were taking place as early as 200 BCE. 

Written accounts from the mid-1500s describe a form of variolation used in China known as insufflation, where smallpox scabs were dried, ground and blown into the nostril using a pipe.

It wasn’t until May 1796 that the world’s first vaccine was demonstrated, using the same principle as variolation but with a less dangerous viral source, cowpox. Having heard of local beliefs and practices in rural communities that cowpox protected against smallpox, Dr Edward Jenner inoculated 8-year-old James Phipps with matter from a cowpox sore on the hand of Sarah Nelmes, a local milkmaid.

Not everyone was on board with Jenner and his vaccine. Rumours circulated at the time that it would turn people into cows. But by 1801, through extensive testing, it was shown to effectively protect against smallpox. 

The vaccine was soon in use on other continents, where vaccine continued to be inoculated from arm to arm until vaccination programmes were established. Mandatory smallpox vaccination came into effect in Britain and parts of the United States of America in the 1840s and 1850s, as well as in other parts of the world, leading to the establishment of the smallpox vaccination certificates required for travel.

In 1958, the World Health Assembly called for the global eradication of smallpox – the permanent reduction to zero cases – without risk of reintroduction. 

Efforts were redoubled with the launch of the Intensified Smallpox Eradication Programme in 1967. The Soviet Union provided freeze-dried vaccine, which became the basis for elimination of smallpox from eastern Europe, China and India. 

With renewed political commitment and the contributions of hundreds of thousands of local surveillance officers and health workers, even regions with nascent health systems and tremendous logistical challenges made remarkable progress.

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. British, Canadian, Cuban, French, Soviet, and US vaccines were given freely to WHO and distributed onwards, sometimes with the strategic financial support of Sweden.

Through all this, the United States and the Soviet Union worked in rare solidarity. It was an unprecedented demonstration of global unity in the face of a common threat. As a major contributor to the programme, the United States reportedly recoups their investment every 26 days in money not spent on administering further vaccinations and treating new cases. 

Instead, following the discovery of Dr Jenner’s vaccine, eradication was achieved through prevention, as he himself predicted. Bolstered by efforts united around the world, Jenner’s concept survived to defeat a historic scourge.