She went on to earn a BSc in chemistry and mathematics and then a PhD in chemistry at the University of Cape Town. From 1983 to 1986, she pursued post-doctoral studies at Pennsylvania State University. Mizrahi then worked in research and development for pharmaceutical company Smith, Kline & French. In 1989, she established as research unit at the South African Institute for Medical Research and University of the Witwatersrand, remaining there until 2010. Her research has been focused on the treatment of tuberculosis, and drug resistance. In 2011, she became director of the Institute of Infectious Disease and Molecular Medicine at the University of Cape Town. Mizrahi is director of a research unit of the South African Medical Research Council and leads the University of Cape Town branch of the Centre of Excellence in Biomedical TB Research.
Mizrahi received the LOréal-UNESCO Award for Women in Science in 2000. In 2006, she received the Gold Medal from the South African Society for Biochemistry and Molecular Biology for her contributions to the field and the Department of Science and Technologys Distinguished Woman Scientist Award. She is a fellow of the Royal Society of South Africa, a member of the Academy of Science of South Africa and a fellow of the American Academy of Microbiology since 2009. She was named to the Order of Mapungubwe in 2007. From 2000 to 2010, she was an International Research Scholar of the Howard Hughes Medical Institute; in 2012, she was named a Senior International Research Scholar for the Institute until 2017. In 2013, she was awarded the Institut de France's Christophe Mérieux Prize for her work in tuberculosis research. Mizrahi was elected a Fellow of the Royal Society in 2023.