Mary Mallon

Mary Mallon (September 23, 1869 – November 11, 1938), known commonly as Typhoid Mary, was an Irish-born American cook believed to have infected between 51 and 122 people with typhoid fever. The infections caused three confirmed deaths, with unconfirmed estimates of as many as 50. She was the first person in the United States identified as an asymptomatic carrier of the pathogenic bacteria Salmonella typhi. She was forcibly quarantined twice by authorities, the second time for the remainder of her life because she persisted in working as a cook and thereby exposed others to the disease. Mallon died after a total of nearly 30 years quarantined. Her popular nickname has since become a term for persons who spread disease or other misfortune, not always aware that they are doing so.