This month in medical history: the tragic life of Typhoid Mary

On Nov. 11, 1938, the most infamous typhoid carrier in medical history died after a quarter century of forced exile. Mary Mallon was born in Ireland in 1869 and worked as a cook for wealthy New Yorkers. In 1906 she was hired by a banker living in a rented house in Oyster Bay, Long Island. When typhoid fever struck 6 of its 11 occupants, the property's owner hired George Soper, a sanitary engineer, to investigate. Salmonella typhosa had been identified in the 1880s. Soper was aware that it spread through contaminated water and suspected the possibility of carriers. He traced Mallon's employment history and discovered that typhoid had struck in 7 of the 8 families she had worked for, with 22 cases between 1900 and 1907.

In March 1907 Soper told Mallon she was spreading typhoid and demanded samples of feces, urine and blood. She refused. Soper enlisted the help of the New York City Health Department but it could not persuade Mallon either. Finally, under police escort, Mallon found herself in the Willard Parker Hospital, where high concentrations of typhoid bacilli were confirmed in a stool specimen.

She was quarantined in an isolation cottage on the grounds of Riverside Hospital in North Brother Island, NY. In 1909 she sued the health department for her release, but it was not granted. However, a year later a new health commissioner released Mallon, based on her promise not to work as a cook.

She didn't keep the promise. Having eluded the authorities, "Typhoid Mary" resurfaced in 1915 when an outbreak of 25 new cases of typhoid occurred at the Sloane Memorial Maternity Hospital, where Mallon was working as a cook under the name "Mrs. Brown." She spent the rest of her life in isolation and died in 1938.

To the end, Mary Mallon rebelled against her incarceration. She maintained that she was healthy and never had typhoid. Her story continues to evoke conflicting emotions and is often cited during debates on the dilemma between the rights of an individual versus the rights of society.