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HENDERSON, DONALD A. 1928-

DIRECTOR OF THE WORLD HEALTH ORGANIZATION
PROGRAM TO ERADICATE SMALLPOX

A Rare Award

In 1976 the United Nations (UN) World Health Organization (WHO) in Geneva received the rarely given Albert Lasker Public Health Service Award for "the imminent eradication of smallpox—the first and only disease ever to be eradicated from the earth." When Dr. Donald A. Henderson, the director of the organization's global smallpox eradication program, accepted the award for the UN agency, he said that only two known smallpox cases existed—in Somalia. Final confirmation of eradication required atleast two years of search in every infected area in the world. A few years later the world became free of this dread disease.

A Global Eradication Program

Henderson was born in Ohio, graduated from the University of Rochester Medical School, and joined HEW's disease-control center, where he worked to control such diseases as measles and smallpox. When President Lyndon B. Johnson decided to offer assistance in smallpox eradication to eighteen countries of western and central Africa in 1965, Henderson was designated the program's director. Six months later WHO asked him to come to Geneva to organize an intensified global eradication program. The goal was to stamp out smallpox in ten years.

A Dread Disease

Smallpox was one of the most terrible diseases known to humankind. Caused by a virus, it led to a high fever and aching pain, and ultimately to disfiguring scabs. Of those infected with the most virulent strain of the disease, 20 to 30 percent died. Those who survived were scarred and sometimes blinded. There was no treatment for the disease, but vaccines, first discovered by Englishman Edward Jenner in 1796, provided some preventive measures. Unfortunately, even when 95 percent of a population was vaccinated, an outbreak continued to spread.

An Enormous Task

The task seemed enormous when Henderson began. But the nature of the disease itself provided the WHO team with the hope of success. The smallpox virus passed from one person to another through face-to-face contact from tiny droplets expelled from the mouth and nose. No animal or insect host was known, and the disease was rarely transmitted via clothing or bedding. A victim usually infected no more than five others, and the disease spread slowly and left its evidence in scarred survivors.

Surveillance Containment

Once enough vaccine was available, reporting techniques had been improved, and outbreaks had been tracked down, Henderson's teams initiated massive vaccination programs. But the most effective approach was a second strategy, called surveillance containment. "Fire-fighting" teams discovered outbreaks, isolated patients, and vaccinated entire villages. By hunting for the source of infection, they found other out-breaks and contained them—breaking, one by one, the chains of transmission. After 1979 Henderson could announce that smallpox no longer was a threat to humanity. But the virus was not extinct. Samples of the organism continued to survive in a few laboratories throughout the world.