An Irish immigrant cook, Mary Mallon, infected as many as 22 people in New York City with typhoid fever
between 1900 and 1907. Mallon, who became known later as "Typhoid Mary," was a carrier of the disease.
This means that she had no symptoms and was otherwise healthy but could spread the infection to others.
(This was before antibiotics were available, which may have been able to kill the bacteria in her body.)
Although she committed no crime, city authorities held Mallon in an isolation cottage on an island in
New York's East River from 1907 to 1910, and then again from 1915 (after it was discovered that she
was responsible for another outbreak of typhoid fever that infected 25 people) until her death in 1938.
She was confined as a threat to public health.
Many decades later, this case still raises an important and difficult question: how far should health
authorities go in restricting individual rights to protect the general welfare of the public?