The Imprisonment of Typhoid Mary, 1907 – A Typhoid Outbreak

In 1907, Typhoid Mary became known in the United States as an apparently healthy person responsible for an “outbreak”. She was the first such person identified, and her imprisonment also made her central to debates about confining disease carriers for life.

Typhoid is caused by Salmonella enterica serotype typhi, also known as S. typhi. It is an acute systemic infectious disease. This bacterial subtype infects only humans. Infection may follow consumption of food or water contaminated with urine or faeces from people with acute typhoid or chronic carriers. Symptoms may include:

• High fever
• Diarrhoea or constipation
• Fatigue
• Muscle pain
• Skin rashes 

In 1948, treatment for typhoid fever began to use chloramphenicol. However, resistance to this medicine developed, and typhoid again became an important cause of illness and death. 

Some people can be infected with the bacterium without symptoms. The most famous of these “carriers” was Mary Mallon, also known as Typhoid Mary.

Irish-born Mary began working as a cook in a house in Mamaroneck, New York. However, 2 weeks after she started, the residents developed typhoid and she had to leave. She repeatedly had to leave her workplaces. In 1906, sanitary engineer George Soper discovered that typhoid outbreaks frequently occurred in houses where Mary cooked. By then, she had cooked for 8 families, and typhoid had occurred in 7 of them. 

About 3000 New Yorkers became infected that year, and Mary was thought to be the main source. Sober, who investigated the events while considering her work as a cook, became the first person in the United States to identify a carrier of Salmonella typhi who was a “healthy carrier”. He published his findings in the Journal of the American Medical Association (JAMA).

Mary was arrested, and examination of a forcibly obtained stool sample confirmed that she carried typhoid. In 1910, she was released but completely prohibited from cooking. Ignoring the decision, she changed her surname to Brown and began cooking at Sloane Hospital in Manhattan. Within three months, she infected at least 25 people. After this, she was labelled “Typhoid Mary” (English: “Tifoid Mary”) and entered the medical literature as a disease carrier. 

Historians hold Mary responsible for at least 50 typhoid cases (and at least three deaths), although the people she infected are thought to have infected many more. 

Mary was sentenced to lifelong quarantine in the hospital where she had previously been quarantined. Mary Mallon stayed at Riverside Hospital during the 6 years in which she was paralysed and died in 1938. The much-debated case brought attention to the importance of epidemiology (the study of factors affecting population health) in shaping public policy.

Chlorinated drinking water reduced typhoid incidence in the United States, and the disease can now be treated with various antibacterial medicines (antibiotics). Nevertheless, it remains common worldwide, especially in areas with inadequate infrastructure and hygiene.

Article image caption: A warning poster showing how Typhoid Mary spread disease.

Historical figures mentioned: Mary Mallon (1869–1938), George A. Soper (1870–1948)

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