In 1936, Max Theiler, Professor of Epidemiology and Public Health at Yale (and later the Rockefeller Institute), and his colleagues developed a live attenuated vaccine for yellow fever using tissue cultures prepared from embryonated chicken eggs. Theiler published results of U.S. vaccine trials in humans in 1937. The vaccine was easily adapted for mass production and became the universal standard.

Yellow fever is a viral infection spread by mosquito species common to areas of Africa and South America. Theiler, and Andrew Watson Sellards showed in 1926, that the L. icteroides obtained from Noguchi was serologically identical with L. icterhemorrhagica. In that same year, the Rockefeller Foundation quietly discontinued its distribution of the vaccine, and there was no alternate candidate.

In 1951, Theiler was awarded The Nobel Prize in Physiology or Medicine 1951 “for his discoveries concerning yellow fever and how to combat it.”