In the early years of the 20th century, Mary Mallon was known in the wealthy houses of New York and Long Island mainly for her good cooking skills.
Mallon was born in 1869 in Ireland, but a terrible famine in her country forced her to flee to the United States when she was only 15.
Initially, her work as a cook offered her a quiet life, but the story of the Irish emigrant was truncated when the Americans began tracing the transmission of typhoid fever in 1907. All cases pointed to her.
The first asymptomatic carrier
In 1900, Mary Mallon had been working as a cook for only two weeks in a house in Westchester, New York, when every resident contracted typhoid fever.
From 1901 to 1907, the same situation was repeated in the different houses in which she was hired. No place seemed safe, the real panic began when the disease hit the family of the wealthy banker Charles Warren.
Typhoid fever was linked to rather poor neighbourhoods, depressed areas where overcrowding and lack of hygiene caused serious health problems, but cases in wealthy families surprised doctors and researchers.
Frightened, the owner of the house in which Charles Warren was residing hired the services of civil engineer George Soper, to whom he notified that the cook had left the job.
The engineer investigated the houses where Molly had worked before and realized that the reason for the contagion was Mary herself: an asymptomatic person, someone capable of transmitting the disease bacteria without first presenting a febrile symptom and, which is worse, without being aware of it.
An unprecedented form of isolation
The tests carried out on the Irish cook led to certain suspicions of the American engineer, forcing her into an isolated hospital room.
After attacking a doctor with a fork and beating an unsuspecting police officer, the New York City Department of Health banished Mary Mallon in 1907 to a small island where her quarantine period would begin. In it, the cook lived in a cabin attached to Riverside Hospital in the sole company of a dog.
Mary Mallon received food daily so that she could cook it and eat it in the strictest solitude.
The quarantine, which lasted for three long years, came to an end in 1910 when a new health inspector decided to lift Mallon’s imprisonment, on the sole condition that she would not return to work as a cook.
By that time, the media had already echoed the case and had begun to call it Typhoid Mary, describing it as a stubborn woman with a bad personality, unable to recognize the contagions she was causing.
Mary Brown, a new identity
Mallon, perhaps unaware of her true responsibility, breached the commitment and under the name of Mary Brown continued to work in the kitchens of hotels, restaurants and institutions.
It was then that in 1915, a new outbreak of typhoid fever in a Manhattan hospital, affecting 25 workers, gave away the cook despite her false name.
Engineer Soper managed to recognize the Irish font and on 27 March of the same year, the authorities launched the second quarantine of the asymptomatic carrier, thus beginning another 23 years of isolation that would end with her death at 69 years.
Nowadays, it is assumed that the cook Mary Mallon, without ever having shown any symptoms of the disease (fever, headaches, diarrhoea…) infected 53 people, three of whom died.