Gertrud Theiler Prize in Physiology or Medicine for development of the yellow fever vaccine. Gertrud Theiler Gertrud Theiler (11 September 1897 – 2 May 1986) was a South African parasitologist and teacher most noted for her work with nematodes and ticks. Born on 11 September 1897 in Pretoria, South Africa, Theiler graduated from Pretoria Girls’ High School and spent a year at Rhodes University College in Grahamstown, South Africa, before transferring to South African College in Cape Town, where she graduated in 1918 with a Bachelor of Science degree. She went to Europe to undertake postgraduate work in helminthology at the University
Max Theiler War II. Subculturing the particularly virulent Asibi strain from West Africa in chicken embryos, a technique pioneered by Ernest Goodpasture, the Rockefeller team sought to obtain an attenuated strain of the virus that would not kill mice when injected into their brains. It took until 1937, and more than 100 subcultures in chicken embryos, for Theiler and his colleague Hugh Smith to obtain an attenuated strain, which they named "17D". Animal tests showed the attenuated 17D mutant was safe and immunizing. Theiler's team rapidly completed the development of a 17D vaccine, and the Rockefeller Foundation began human trials in South