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History of Medicine

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Smallpox: A Great and Terrible Scourge banner
Smallpox: A Great and Terrible Scourge written in white lettering with a black border Public Health Service Historian History of Medicine Division National Library of Medicine National Institutes of Health The Threat written in red letters. Variolation written in red letters. Vaccination written in red letters. Resistance to Vaccination written in red letters. The 20th Century Threat written in red letters. Campaign to Eradicate written in red letters. Obstacles and Struggle written in red letters. Success written in red letters.

The 20th Century Threat

Despite a dramatic decline in smallpox during the nineteenth century, the disease still posed a threat at the beginning of the twentieth century. Expanding trade networks as well as the rise of immigration and leisure travel meant that smallpox could spread more easily and more rapidly than ever before.

Westward bound - scenes on an immigrant train showing immigrant inspection service, with a doctor vaccinating a baby for smallpox while its mother holds it.

Detail from Westward bound - scenes on an immigrant train showing immigrant inspection service, with a doctor vaccinating a baby for smallpox while its mother holds it.

Whether traveling on boats or trains, immigrants were often required to undergo vaccination.

By the 1960s, smallpox was limited to Brazil, West-Central Africa, East-Southern Africa, the Indian subcontinent and Indonesia. Throughout the world, vaccination programs cost millions and in some cases even resulted in deaths. Although there were calls for the global eradication of smallpox, most people doubted this could be done and the 1967 launch of the World Health Organization’s program to eradicate the disease was met with skepticism.

The title of the illustration states flight #1 and Smallpox. The illustration shows the detail of a flight from Hong Kong to New York and the stops along the way.

The detail of an illustration showing the flight path with the stop in London and one case reported of smallpox. In the center it says Hong Kong to New York 36 hours, smallpox incubation 14-21 days.

With the rise of air travel, smallpox could spread across continents and oceans within forty-eight hours or less.

As smallpox became less common, Americans became lax about vaccination. In 1947, when smallpox erupted in New York City, only a quarter of the city’s population had been vaccinated. In the following two weeks, a record 6.35 million people were vaccinated and the epidemic was arrested, leaving only two dead from the disease but six dead from complications related to vaccination.



The specters of cholera, yellow fever, and smallpox recoil in fear as their way through the Port of New York is blocked by a barrier on which is written 'quarantine' and by an angel holding a sword and shield on which is written 'cleanliness.'

An angel holding a sword and shield on which is written 'cleanliness.'

In America, native-born populations feared that immigrants would bring disease into the country. Smallpox was especially feared.

A PHS officer examines a smallpox vaccination take on the arm of a woman at a checkpoint for Cuban refugees at Port Everglades, Florida.

Customs officials checked passengers for vaccination scars to ensure that they had been vaccinated against smallpox.

Last Reviewed: March 5, 2024