1media/Max_Theiler_nobel (1)_thumb.jpg2024-07-18T22:32:35+00:00Ivan Portillo741ad6f42573dbb784db9511d4627772eb86aa193674Max Theiler, a South African virologist, weakened the yellow fever virus by passing it through mouse and chicken embryos. This process rendered the virus less capable of causing disease while still inducing protective immunity. Theiler's work resulted in a safe and effective yellow fever vaccine, which remains used today. Image Attribution: Public domain, via Wikimedia Commonsplain2024-07-19T16:47:33+00:001937Ivan Portillo741ad6f42573dbb784db9511d4627772eb86aa19