Alan earned his undergraduate degree from Cornell University, his medical degree from Western Reserve University, and a Masters of Public Health from Harvard University. Since 1965, Alan has been involved in public health programs at the state, national, and international levels, primarily working with the Centers for Disease Control and Prevention (CDC), where he served as Director of both the Immunization Division (1977-1988) and the National Center for Prevention Services (1988-1995). In addition, he has worked for the state health departments of New York and Tennessee.
After rising to the rank of Assistant Surgeon General, Alan retired from the national public health service and joined the Advisory Group of The Task Force for Global Health in 1996. In addition to authoring or co-authoring more than 400 publications, he served on the Board of Gavi, the Vaccine Alliance, as well as Chairing a WHO Advisory Committee. Currently, he is a professor in Global Health and Epidemiology at the Rollins School of Public Health of Emory University.