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May 10, 2018

The Cook Who Killed: Revolutionized Public Health

Summer of 1906 brought about an unexpected arrival into the Warren’s rented summer household when “… one of the Warren’s daughters became ill. Next, two maids and Mrs. Warren were affected followed by another daughter and the gardener.”1 While summer vacationing in a wealthy neighborhood of Oyster Bay, Long Island, six members in a household became gravely ill with typhoid fever. Prior to this infection case, many people associated typhoid fever infections were usually from the lower class because typhoid was known to be caused by poor sanitation of water and food. The Thompsons, who rented their house to the Warren family, hired George Soper to investigate the cause of the typhoid fever outbreak in the household. They were afraid their house would never be rented again because it was contaminated with the bacteria causing typhoid fever. Soper was a distinguished scholar who had attained his Ph.D in the field of Sanitary Engineer. His previous work with the typhoid epidemic made him vital as an epidemiologist working for the Department of Health.2

Salmonella Typhi (Typhoid Fever bacteria) under a microscope | Courtesy of Global Security

Soper began by thoroughly and systematically investigating all the known facts that had been presented to him, and one by one he ruled out all types of potential sources of infection. Finally, he found that the family had changed cooks prior to the family’s typhoid fever attack.3 Due to Soper’s previous medical investigations, he was well aware that a person can be a healthy carrier of certain diseases, and typhoid was one of them. This means that a person could be infected by some type of a pathogen and they would not demonstrate any symptoms. Due to this, the person would seem healthy and not a menace to society. While the person may seem healthy, they can become the driving force that helps spreads the pathogen. This phenomenon occurs in about 3% of patients who recover from the bacterial infection that causes typhoid fever.4

Bacteria have evolved alongside humans in order to successfully infect themselves into a human host. Pathogens continue to spread into the human population, which can be seen in the case of Salmonella typhi that infected Mary Mallon, the family’s cook. Though she was never gravely ill from her infection, the pathogen had embedded itself within her body and it used her as a vessel to bring the infection to many unsuspecting people. Due to the number of people she infected, she became known as Typhoid Mary as she unknowingly infected fifty-one people with her cooking, which ultimately led to the deaths of three people.5

Mary Mallon, an Irish immigrant, became the first known asymptomatic carrier of typhoid fever. Her work as a cook placed everyone who ate her food at great risk of getting typhoid fever.6 A bacterial infection that causes typhoid fever to occur can be passed via fecal matter or contaminated water used to cook food. Once this type of bacteria enters the human body, it primarily lives in the stomach until it progresses into the lymphatic system and finally, makes its way to the bloodstream, where it is spread throughout the rest of the body.7 Mallon posed a great risk to societal health, but more specifically to those she cooked for, especially when she made her famous and well-loved desert peach ice cream. High heat kills the typhoid causing bacteria; however, in cold foods the bacteria is placed in a frozen state. Once in the human body, it metastasizes and eventually enters the bloodstream and there it facilitates its spread throughout the body.

A poster warning against Mary Mallon and how she infects families with her cooking | Courtesy of Flicker

Antibiotics that could treat bacterial infections such as typhoid fever were not introduced to the until the early 1940s. Therefore, during the late 1870s, only the symptoms caused by the infection such as fever, fatigue, joint pain, headache, constipation, and a rash consisting of a rosy pink color spotted across the abdomen could be treated by physicians until the body completely fought off the bacterial infection on its own.8

After Soper tracked down Mallon, who had been employed as a cook for another wealthy family after leaving the Warrens, he asked her for a sample of her fecal matter, as asymptomatic carriers have the bacteria in their stool. He needed the sample in order to properly investigate for the typhoid-causing bacteria so he could soundly confirm that she was the source that infected the Warren’s family. Unfortunately, Mallon refused and chased Soper out of the house, stating that it was impossible for her to be the source. She had never contracted the disease and she had been completely healthy throughout her stay with the Warrens. Even while treating the sick, she never became ill herself.9 Soper’s accusations were not well received because Mallon heavily relied on her cooking skills as her source of income. Furthermore, if she were infecting people with the bacteria known for causing typhoid fever, then she would never be hired as a cook again. Mallon did not know that she was carrying the disease, and more importantly, she did not know that through her cooking she could spread the bacteria, so she could not believe she was infecting anyone through her cooking.

With the help of New York City Department of Health, Soper was able to track down Mallon once again and have her removed from society as she continued to infect the families for whom she cooked. After her removal, she was placed on North Brother Island, an island where many other patients infected with deadly diseases lived because they posed serious health risks for the larger public. Her only crime was being a carrier of typhoid and for this she was sentenced to live on an island. Alongside many other people who carried grave and highly infectious diseases that Mallon was not immune to, she was being placed in an environment that left her vulnerable, free today and held captive on an island the next day. Her freedom was stripped away from her as she was forced to live away from her family, friends, and anyone she knew. While living on this island, Mallon received the help of other doctors who argued not only had the Department of Health grossly abused their power by removing Mallon from society, but they deprived her of her right to happiness, and she planned to sue. Many doctors also argued that if Mallon trained to do another type of job that was not food related, then she would not be able to infect people. The bacteria posed no health threats once outside the host body.10 Mallon challenged America’s Public health system and won. After three years of living in isolation, Mallon was free to go, on one condition: that she may never become a cook again. With the help of the judge who was on her case, she became employed as a laundress; however, this job proved not be as lucrative as her cooking job.

The Department of Health realized that of those who had survive typhoid fever, 3% of them would became asymptomatic carriers of the pathogen. As the number of survivor grew so did the number of asymptomatic carriers. The New York City’s Health Department knew that they had to specially retrain all food handler who had became asymptomatic carriers of typhoid fever. The city also employed other ways of minimizing infection such as paying typhoid fever carriers not to go to work, in efforts to minimize potential typhoid outbreak case.

The city of New York was doing very well until a typhoid fever broke out in a hospital, and twenty-five people become infected with typhoid and two of them died. The source of the bacteria was unknown. When further investigation was conducted by Soper, he found out that some of the other kitchen workers nicknamed the newly hired cook as Typhoid Mary. It was not long until Mallon was found, and in 1915 she was apprehended by Public Health officials. Without a fight she cooperated with the Health department and went to live on the island she had successfully and legally left, only to return four years later.11 The moment she broke the only agreement with the judge was the moment that sealed her fate. She was allowed to leave the island periodically to visit family, shop, and integrate herself into society away from the island, while being supervised.

A poster warning against Mary Mallon and how she infects families with her cooking |Courtesy of Flicker

The name Mary Mallon might be lost in the pages of history, but the infamous Typhoid Mary will continue to live on as the first known carrier of typhoid. Throughout her debacle she fought for her human rights and was unafraid to challenge the Health Department’s approach to people who were asymptomatic carriers of typhoid fever. Her story will forever be a potent symbol of America’s fear of diseases.

  1. Judith Walzer Leavitt, Typhoid Mary (Beacon Press, 1996), 15.
  2. Judith Walzer Leavitt, Typhoid Mary (Beacon Press, 1996), 15.
  3. Judith Walzer Leavitt, Typhoid Mary (Beacon Press, 1996), 16.
  4. Encyclopedia of Medicine, 2016, s.v. “Typhoid Fever.”
  5. Encyclopedia Britannica, November 15, 2017, s.v.”Typhoid Mary.”
  6. Jennifer Ashley Wright, Get well soon: History’s Worst Plagues and the Heroes Who Fought Them (New York : Henry Holt and Company, 2017), 77-79.
  7. Encyclopedia of Medicine, 2016, s.v. “Typhoid Fever.”
  8. New World Encyclopedia, 2017, “Typhoid Fever.”
  9. Judith Walzer Leavitt, Typhoid Mary (Beacon Press, 1996), 15.
  10. Encyclopedia of Medicine, 2016, s.v. “Typhoid Fever.”
  11. NPR.org, October 30, 2014,  Awful Moments In Quarantine History: Remember Typhoid Mary?

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Recent Comments

79 comments

  • Marina Castro

    This article was very interesting to read because of how strange the story was. It is also a little bit scary to read because you never know who is cooking your food. At least out of a horrible tragedy like this something good came out of it. Today that would be very unlikely to happen because of the many regulations that exist.

  • Luis Magana

    I love the title of the article it gives it suspense, but the disease of typhoid was a highly contagious and dangerous disease. I can’t believe that Mary didn’t realize she was getting everyone she had worked for sick. It shows how ignorant people can be. She gave more importance to her job than the health of her clients. How could someone just disobey the judges orders and just found a different way to make money. Maybe if she listened two lives would not have been lost.

  • Maggie Amador

    The idea of being a carrier has always terrified me because of the threat you can serve to those around you. It’s ridiculous the way Mary was treated and isolated from society due to something out of her control. I am interested in learning more about North Brother Island and the conditions those placed on the island had to go through. Although I am glad science has come a long way and we as a society are better equipped to handle asymptomatic carriers, the fear of being an unsuspecting carrier still remains valid.

  • Kristy Feather

    I didn’t know that people could be carriers the way Mary was. I knew that diseases were exchanged by bodily fluids, but to think that one person could be a permanent host and can exchange their disease to others threw the food they cook is both fascinating and terrifying. What’s even more terrifying, is that a host could be put to jail just for being a carrier of the disease. She couldn’t control her own blood and yet she was punished for it. I do understand why it happened the second time. If you know you are a catalyst for illnesses then willingly going against what the courts told you and spreading it to so many people is purposely harm. The moment two people died because of her decision, Mary became a murderer.

  • Natalie Juarez

    At first, I felt bad for Marry Mallon because she was forced to leave her home to live on an island with other people she did not know, who were ill and removed from their homes. I was disappointed when she decided to break her promise to never cook again, which resulted in her infecting people with Typhoid, but then again, I can’t imagine what life was like for her to be an asymptomatic carrier of the fever. This was a well written and informative article that tells the story of the first known carrier of typhoid, Marry Mallon, and how her life was affected by it and numerous others.

  • Lamont Traylor

    This article was very interesting and strangely terrifying because this relates to everyone who has food cooked for them on a daily basis such as students of any school and elderly people. People at buffets, rich people with chefs, and any other people who have cooks should be terrified also. What is even scarier than the topic is that as humans evolve to stop disease and bacteria, the bacteria evolve to get past our barricades.

  • Daniela Duran

    This was a very interesting article, with a lot on scientific insight that made things clearer and easier to understand. I am really impressed by how someone can be carrier or such a serious disease, but be completely unaware of it! I agree with Mary that it was not her fault to be a carrier, and she did not deserve to be put into an island because of that. I consider that the judge did the right thing by letting her free but prohibiting her job as a cook. However, it was quite irresponsible from Mary to disobey the rules of the judge, and although I understand her economical needs, perhaps she could have found a different job to laundry and cooking. If only she had listened to the judge’s request, 2 lives would have been saved…

  • William Rittenhouse

    I remember hearing about this during biology class one day. I found it interesting that Mary didn’t take a hint after every one she had worked for became sick. I know she relied on cooking as her income, but if she was an ethical thinker she would have stopped what she was doing and try to figure out if she was causing this illness. I’m sure this type of thing still happens today, but just not with as deadly diseases. She valued her job and hapiness more than the well being of her customers.

  • Ariana Melendez

    This article gives insight on the disease of typhoid and its highly contagious nature. Prior to reading this, I was not aware of asymptomatic people. It is interesting to me how these particular people exist, and how they can become that way. For instance, Mary claimed she never had typhoid fever, yet she was a host. Nonetheless, the Health Department fixed their approach towards these people to a more positive one.

  • Nathan Alba

    I found the article to be written well. I did find it hilarious when Mallon chased Soper away after asking for a stool sample. However, it was an important case because at the time who would have known that a human host could seem perfectly fine and without symptoms but still be spreading the bacteria in large amounts. It’s unfortunate that Typhoid Mary had to be put on an island and be quarantined, but at the time there were no further treatments for the issue. Although Typhoid Mary accidentally killed the people she cooked for, she helped out scientists understand the nature of pathogens and their deadly properties.

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