Alice Evans identified the organism causing undulant fever. This discovery, one of the most medically important in the early 20th century, led to laws mandating milk pasteurization, saving countless lives in America and throughout the world.
Evans, one of the first woman scientists to hold a permanent appointment in the USDA Bureau of Animal Husbandry (she later worked at the National Institute of Health), initiated her studies of bacterial contamination of milk in 1910 and revealed her findings in 1917. Fierce opposition to her results developed but in the 1930s, milk pasteurization laws were enacted.
Although she was herself infected with undulant fever in 1922, she worked throughout her life as a widely-respected scientist, serving as the first woman president of the American Society of Bacteriologists.
After retirement in 1945, Evans lectured frequently on female career development, emphasizing scientific careers.