American physician and public health activist Sara Josephine Baker was BOTD in 1873. Born in New York City to a wealthy Quaker family, her father and brother died when she was in her teens, and she pursued career in medicine to support her mother and sister. She practised as a physician before becoming a public health inspector, investigating the spread of typhoid and gonorrhoea and helping identify Mary Mallon as “Typhoid Mary”. Working primarily in the slums of New York, she educated families on hygiene and lowering infant mortality. Known as “Dr Joe”, she wore masculine tailored suits and joked that colleagues frequently forgot she was a woman. She became a lecturer in child hygiene at New York University Medical School, later becoming the first American woman to receive a doctorate in public health. In 1917, she made national headlines when quoted saying that American babies had a higher mortality rate than soldiers fighting in World War One, attracting widespread support for her campaign for public health funding. She was promptly appointed Assistant Surgeon General, becoming the first woman to hold a federal government position. Following her retirement from medicine in 1923, she represented America in the League of Nations, remaining active in the New York State Department of Health, becoming the president of the American Medical Women’s Association, and publishing a memoir and innumerable public health articles. Baker lived for much of her adult life with Ida Wylie, an Australian-born novelist and screenwriter who identified as a “woman-identified woman”. In 1935, she and Wylie moved to Princeton, New Jersey with their friend, the pathologist, feminist and fellow bachelorette Louise Pearce. Baker died of cancer in 1945 aged 71. Now recognised as a pioneer in the development of public health and preventative medicine,