Believed to have been born in the United States about 1870, Mary Mallon allegedly gave rise to the most famous outbreaks of carrier-borne disease in medical history. She was first recognized as a carrier of the typhoid bacteria during an epidemic of typhoid fever in 1904 that spread through Oyster Bay, New York, where she worked as a cook. By the time the disease had been traced to its source in a household where she had recently been employed, she had already left. She continued to work as a cook, moving from household to household, until 1907, when she was found working in a Park Avenue home.
Between 1907 and 1910 she was institutionalized at Riverside Hospital on North Brother Island (in the East River), New York City, the authorities of which finally released her on the promise that she would seek employment other than a cook. Four years later, after another outbreak of typhoid fever, she was found to be working as a cook in a sanatorium in New Jersey, and after that she remained in detention on North Brother Island until her death in New York City on November 11, 1938. Her history as a carrier implicated her in 3 deaths from typhoid and more than 50 other cases, while, as is not uncommon, she herself remained immune.
