Variolation shortly after variolation began to outweigh the benefits of the procedure. From the 1760s, a number of individuals, including John Fewster, Peter Plett, Benjamin Jesty, and particularly Edward Jenner, were interested in the use of material from cowpox, an animal infection, to protect against smallpox. In 1796, Jenner vaccinated James Phipps, did more vaccinations in 1798, and was the first to publish evidence that cowpox protected against smallpox, was safer than variolation, and that his vaccine could be maintained by arm-to-arm transfer. The use of variolation soon began to decline as the smallpox vaccine became widely used and its benefits
Donald Henderson United States Agency for International Development (USAID) program to eliminate smallpox and control measles during a 5-year period in 18 contiguous countries in western and central Africa. This project was funded by USAID, with field operations beginning in 1967. The USAID initiative provided an important impetus to a World Health Organization (WHO) program to eradicate smallpox throughout the world within a 10-year period. In 1966, Henderson moved to Geneva to become director of the campaign. At that time, smallpox was occurring widely throughout Brazil and in 30 countries in Africa and South Asia. More than 10 million cases and 2