In 1949, at Harvard, John F. Enders, Ph.D., a Yale College graduate, Frederick C. Robbins, M.D., and Thomas H. Weller, M.D., using in vitro cultivation, grew poliovirus in non-nerve tissue—a breakthrough that would win them the Nobel Prize in physiology or medicine.

By cultivating these viruses in a test tube, rather than in the brain or spinal column of a monkey, researchers could get a better look at the changes occurring in polio-infected cells. Far more important, a safe reservoir of poliovirus had now been created, free from the contaminating effects of animal nerve tissue. And that, in turn, made possible the mass production of a vaccine.