Who was Typhoid Mary?

Mary Mallon (September 23, 1869 – November 11, 1938), also known as Typhoid Mary, was the first person in the US to be identified as a healthy carrier of typhoid fever. She worked as a cook in New York City. She was an Irish girl who’d migrated to the US for a better life. She infected nearly 53 people, three of whom died. At first, when a health inspector found her to be a carrier, she was isolated for three years at a hospital and after that she was released on the condition that she would not work with food. But, she found work as a cook in a hospital, this time under the name Mary Brown. This time, health inspectors quarantined her for life. Now, Typhoid Mary has become a generic name for those carrying any dangerous disease without showing of any symptom of it.