Today, people use the name "Typhoid Mary" to refer to anyone who may be unwittingly spreading a disease. But few know the story of the actual Typhoid Mary - Mary Mallon - who, in the early 1900s, was the first person in the US to carry the typhoid fever pathogen.
Mallon was an Irish family cook who became associated with a typhoid outbreak in 1907. It seemed unlikely that she was the source since Mallon displayed no telltale signs of typhoid - abdominal cramping, fever, bloody nose, and hemorrhaging.
Mallon was twice quarantined against her will, during which times doctors confirmed she carried the pathogens. But as she was asymptomatic, Mallon refused to believe her involvement with the outbreaks, which led to a number of confirmed deaths. Watch the video to learn how scientists only recently worked out the mechanism of her dormant disease.