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
Vaccine vaccine is designed to immunize against a single antigen or single microorganism. A multivalent or polyvalent vaccine is designed to immunize against two or more strains of the same microorganism, or against two or more microorganisms. The valency of a multivalent vaccine may be denoted with a Greek or Latin prefix (e.g., "tetravalent" or "quadrivalent"). In certain cases, a monovalent vaccine may be preferable for rapidly developing a strong immune response. Also known as heterologous or "Jennerian" vaccines, these are vaccines that are pathogens of other animals that either do not cause disease or cause mild disease in the organism