Typhoid Mary

Mary Mallon (September 23, 1869 – November 11, 1938), better known as Typhoid Mary, was the first person in the United States identified as an asymptomatic carrier of the pathogen associated with typhoid fever. She was presumed to have infected some 49 people, three of whom died, over the course of her career as a cook. She was forcibly isolated twice by public health authorities and died after a total of nearly three decades in isolation.

• http://en.wikipedia.org/wiki/Typhoid Mary