A brief review of the fascinating life story of Mary Mallon (Typhoid Mary), another famous figure in microbiology.

Mary Mallon was born on September 23, 1869 in Cookstown, Northern Ireland and emigrated to America around the age of 15.

She held various domestic servant positions before finding that her talents lay as a cook, which was a better paid position.

It was not long before suspicions arose that she was the source of illness in people that she was cooking for, and she drew the attentions of the New York City Health Department.

As she was healthy she did not believe that she could be the source of disease and thus resisted attempts at investigation. Eventually she was taken by force and isolated on North Brother Island for a period of 2 years (1907-1909).

During this period she had 163 stool samples taken, of which 120 were positive for Salmonella typhi, the cause of typhoid fever.

She was eventually released on the condition that she never return to work as a cook.

She initially followed these instructions but eventually returned to employment as a cook using a pseudonym (Mrs Brown).

In 1915 following a typhoid outbreak at a maternity hospital, Mary Mallon was discovered to be working there under her pseudonym. She was re-captured by Public Health officials and sent back to North Brother Island, where she remained for the last 23 years of her life. She died in 1938.

For a fuller version of Mary Mallon’s interesting life story, click here.

Mary Mallon’s career choice as a cook was indeed unfortunate, but in general is career choice important? I would answer both yes and no to this one. Yes, because it is clearly important to be doing something that you enjoy doing; No, because it is never, ever too late to change career for something that you really want to do.

Michael