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World Health Organization declares smallpox eradicated

Photo: Poster published by World Health Organization at Geneva, Switzerland, after declaration of eradiction of smallpox on earth, May 8, 1980. AP/Wide World Photos

One of the twentieth century's greatest victories in medicine began in 1796. That year Edward Jenner discovered vaccination. It was known that if a person had smallpox and survived, he or she would not get the disease again. Sometimes people tried to innoculate themselves against smallpox by purposefully contracting a mild case. But Jenner found that if he gave a person serum from a cow (vacca in Latin) that had cowpox, a virus similar to smallpox, then that person was protected from smallpox without having to be exposed to the disease itself. Jenner immediately envisioned the vaccine erasing smallpox from the earth. But it would take another 150 years.

At the turn of the twentieth century, smallpox was still a dangerous disease worldwide. In spite of the proven effectiveness of Jenner's vaccine, other methods of treatment and protection were tried. An especially popular one was treating the disease with red objects and light. This therapy dated back to tenth century Japan and was still in use in the United States in the early twentieth century and in Europe through World War I.

The smallpox vaccine did spread, but slowly. It was initially in short supply and hard to store, especially in hot climates. In the 1920s, French and Dutch researchers developed a dried vaccine for use in their colonies. It was hardier, but the quality was inconsistent. A virulent outbreak of smallpox in New York City in 1947 surprised everyone and inspired a new method to improve the vaccine. Freeze-drying was used successfully in 1949 and brought into commercial production by 1954. Freeze-dried vaccine could last for months, even without refrigeration in tropical climates.

Some localized areas and even some nations had gotten rid of smallpox entirely, but a plan for global eradication was slow to take hold. In 1948, the World Health Organization (WHO) took over the health functions of the League of Nations, at a time when smallpox was still a threat in at least 90 countries. In 1958, WHO adopted a resolution put forth by the Soviet Union to attempt global eradication, but nothing much happened. Finally in 1966, a resolution sponsored by several countries -- including the United States and Soviet Union -- was adopted, and a specific goal set for wiping out smallpox within ten years.

There were then 44 countries still reporting the disease. The Smallpox Eradication Program (SEP) started by tackling some of the poorest countries, determined to score a psychological victory by showing smallpox could be eliminated even where health services were scant. This worked, and led to a major discovery: the disease could be removed without vaccinating every single person. Improved technology (needles that were easier to clean and use, for example) also made delivering the vaccine more efficient. Wars and political uprisings slowed progress, but year after year, new countries announced they had seen their last case of smallpox.

The last naturally-occurring case of smallpox in the world was contracted in October, 1977 by a young man in Merka Town, Somalia. He survived, and no new cases were reported in Somalia or elsewhere. But ironically, in 1978 two more cases popped up in Birmingham, England, from smallpox virus escaped from a research lab. One of the patients died. The director of the laboratory committed suicide. These were smallpox's last victims. In 1979, a global commission certified that smallpox had been eradicated, and this certification was officially accepted by the 33rd World Health Assembly in 1980.

Copyright notice: The photo above is copyright protected and is the property of the Associated Press. Any use without prior written permission from AP/Wide World Photos is prohibited. Any violation will be subject to legal action.

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