Wherever she used to go, there was typhoid fever, so many people suffering, but she was not suffering. So by analysis of the blood, it was found that this girl, the blood was full of typhoid germs, but she was so strong that she could resist. She was not suffering, but wherever she used to go, everyone was infected with typhoid. So that is the explained. Karanam guna-sango ‘sya [Bg. 13.22]. If you are strong enough, then the lower qualities will not affect you. And if you are not strong, if you are weak yourself, then where you are going to convert, they will induce their infectious quality, and you will be victimized.

From Srila Prabhupada’s lecture on Srimad-Bhagavatam 6.1.44 — June 10, 1976, Los Angeles

Typhoid Mary
byname of Mary Mallon
born 1870?
died Nov. 11, 1938

U.S. carrier of typhoid. A 1904 typhoid epidemic on Long Island was traced to households where she had been a cook. She fled, but authorities finally caught up with her and isolated her on an island off the Bronx. In 1910 she was released after agreeing not to take a food-handling job, but she did, causing more typhoid outbreaks. She was returned to the island for the rest of her life. Three deaths and 51 original cases were directly attributed to her.