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Populations: History



In 1959, the World Health Organization committed itself to a bold challenge: Eradicate smallpox. “A lot of people thought it could not be done,” says D.A. Henderson, former dean of the School. Smallpox had plagued humanity for more than 3,000 years, and more than half the world’s population still lived in regions where it was endemic. However, the smallpox vaccine was remarkably effective. WHO officially launched its eradication program in 1966, with Henderson as its chief. Around the world, networks of health clinics and hospitals began reporting every single case of smallpox; health workers then tried to vaccinate all the patients’ possible contacts. 

It worked. On October 26, 1977, a Somali cook named Ali Maow Maalin (left) became the last known person on earth to contract smallpox naturally. On May 8, 1980, the disease was officially declared eradicated. But that victory is haunted by the continued existence of smallpox virus in laboratories—potential biological weapons.



In the second half of the 20th century, overpopulation was approaching the crisis stage in many developing countries. Henry Mosley, supported by the U.S. Agency for International Development,  proved in the late 1970s that even societies without modern medical and economic infrastructures could successfully reduce population growth. In Matlab, Bangladesh (right), his team trained local women to help provide and explain to other women a wide range of birth control choices—condoms, pills, IUDs, and sterilization. In two years, Matlab’s birth rate dropped an astounding 25 percent. Says Mosley, a former chair of the School’s Department of Population Dynamics: “These results influenced family planning around the world.”


William Henry Welch

He came to be called the “statesman” of America’s public health movement. William Henry Welch,  a professor of Pathology and former dean of the medical faculty at Hopkins, had dreamed for almost 30 years of developing an institute of hygiene when the Rockefeller Foundation in 1914 announced its desire to create a professional basis for public health training and practice. The challenge inspired a wide-ranging debate over the relative roles of research, teaching, laboratory science, and fieldwork as well as the profession’s relationship to medicine. In 1916, Welch won the foundation’s support to establish at Hopkins the first independent school of public health in the United States, shaped by a dual commitment to the study and protection of health and to the study and control of disease.