From Pennsylvania farm girl to true heroine of American microbiology, Alice Catherine Evans (1881 – 1975) made one of the most medically important discoveries of the 20th-century. Unable to afford college, she started her career in 1901 as an elementary school teacher. But when Cornell University offered a free class on nature to rural teachers, Alice jumped at the chance and the course of her life (and history) subsequently changed.

While taking that nature class, Alice also took a basic course in the Agricultural College, which started her interest in bacteriology. Fast forward to winning a scholarship to Cornell, earning a Bachelor of Science degree in bacteriology (1909) and a Master of Science degree in the same field from the University of Wisconsin (1910), Alice landed a job in the Dairy Division at the U.S. Department of Agriculture Bureau of Animal Husbandry.

Her work involved investigating bacteriology in milk and cheese. When her appointment was made permanent in 1913, Alice became the first woman scientist to have a permanent appointment in that division of the USDA.

Her findings were not taken seriously by other scientists for two reasons: she was a woman and she didn’t have a PhD.

In 1918, through her pioneering research, she was able to show that drinking raw (unpasteurized) milk could transmit the bacterium, Bacillus abortus, which caused brucellosis (a.k.a. undulant fever or Malta fever), an infectious disease passed from domestic farm animals to humans. As a result, Alice passionately advocated for the pasteurization of milk to effectively kill this disease-causing bacterium.

Her findings and recommendations were not taken seriously by other scientists for two reasons: 1) she was a woman and 2) she didn’t have a PhD. With all the harsh and constant criticism her research received, Alice had a really difficult time convincing physicians, public health officials, veterinarians and farmers that pasteurization was needed to halt the spread of this disease.

Alice C. Evans - 1945

But by the late 1920s, other scientists eventually came to the same conclusion as Alice, and by the 1930s, the United States government passed laws requiring that milk be pasteurized to prevent the disease. So while it took power in numbers to effect change, it was Alice’s discovery that hastened the spread of the pasteurization movement and, as a result, saved countless people from fever and death.

Ironically and sadly, Alice herself contracted chronic brucellosis in 1922, as a result of her research. She suffered from recurrent bouts for years, going through periods of illness and remission because the disease never left her system.

After leaving the Department of Agriculture, Alice worked for the U.S. Hygienic Laboratory where she made valuable contributions in the field of infectious illness, including meningitis and streptococcal infections. In 1928, she became the first woman president of the Society of American Bacteriologists (now the American Society for Microbiology). When she retired in 1945, Alice lectured widely to women about career development and encouraged women to pursue scientific careers.

Alice Catherine Evans died from a stroke in 1975 at the age of 94. She was inducted into the National Women’s Hall of Fame in 1993.

Sources: Library of Congress – Notable Women In Science Knowledge Cards, Authored & Created By Aimee Hess; National Women’s History Museum. Images via Wikipedia, public domain.