Yellow fever vaccine Foundation to improve the vaccine from the "Asibi" strain, discovered that a favorable chance mutation in the attenuated virus had produced a highly efficacious strain that was named 17D. After field trials in Brazil, over one million people were vaccinated by 1939, without severe complications. For his work on the yellow fever vaccine, Theiler received the 1951 Nobel Prize in Physiology or Medicine. Only the 17D vaccine remains in use today. The outbreak of yellow fever in Angola in January 2016 has raised concerns about whether the global supply of vaccine is adequate to meet the need during a large
Yellow fever vaccine neurologic complications in a few cases. Attempts to attenuate the virus used in the vaccine failed. Scientists at the Rockefeller Foundation developed another vaccine derived from the serum of an African named Asibi in 1927, the first isolation of the virus from a human. It was safer but involved the use of large amounts of human serum, which limited widespread use. Both vaccines were in use for several years, the Rockefeller vaccine in the Western hemisphere and England, and the Pasteur Institute vaccine in France and its African colonies. In 1937, Max Theiler, working with Hugh Smith at the Rockefeller