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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

  • Nathan Hartley

    At first, when the symptoms were presented, I would have thought that it was food poisoning. I was unaware that somo0ne could carry diseases and be a completely healthy person. I think this article shows why we can never be too careful when we deal with our health, you never know when an outbreak might happen or when it may affect you.

  • Aneesa Zubair

    I was drawn to this article because I’m really interested in public health, and you picked a great topic. You told Mary Mallon’s story very effectively, from her accidental contamination of the Warrens’ food to her imprisonment on North Brother Island to her integration into society. I initially felt sorry that she had to be locked up on an island, but she also shouldn’t have started cooking again when she knew she was infected with typhoid and could cause illness in many other people.

  • Tyanne Pearcy

    This article gave a lot of insight on how health violation in restaurants started. Mary knew that she had typhoid fever therefore support the health departments decision to take her out of the equation. What I found interesting about the typhoid fever is that back in the 18th century they didn’t have the medicine that we have today, so their bodies had to fight the symptoms. But the concerning part of the story is the amount of carriers that were unable to be identified.

  • Adrian Cook

    I thought this was just a case of food poisoning which I’m sure everyone has suffered from in their lifetime but it wasn’t. Mary was never supposed to be handling food because of her illness but she still did it anyway. These victims must have been suffering because I know how bad food illness can be and I’m sure there was no cure to it like we have today. It was a very interesting article that I enjoyed reading.

  • Indhira Mata

    This article was very interesting to me as I am in General Biology. Scientists have found that many people have stronger immune systems to certain bacteria than others and that is how it can hide in their bodies without them knowing. The scary part is that the bacteria can hide until it is triggered by something or can spread itself to others. At this point in time this information was new to our society so that is why their solution was to isolate them. Although it is saving millions, it is against human rights because the carriers can’t do anything to prevent it. Till this day, we don’t know how to solve some bacteria and our solution will be to isolate them which is unfair therefore, this story helped show that we need to help people who are carriers.

  • Mariana Valadez

    When I saw the title of this article I was intrigued. It is very scary that Mary Mallon caused people to be ill and that it could’ve been prevented be her being a little more hygienic. Although she was unaware of her illness, when she found out she continued to work with food. She was told she couldn’t go near food but did anyways.

  • Karina Cardona Ruiz

    This was my first time hearing of Mary Mallon and I found her story to be an interesting read. Perhaps she could’ve prevented the infection of others by just having better hygiene and wearing gloves when she cooked. I don’t think she intentionally tried to harm people initially considering that she was unaware that she was a carrier of the typhoid pathogen. However, after she had been informed she choose to go back to cooking just so she could make more money which was unacceptable considering the circumstance.

  • Janelle Larios

    The title of the article really caught my attention. I had never heard about this in any shape or form. So reading this article was a trip for me. I was surprised that a development in public health could only be brought by a cook who didn’t even know. Even then I didn’t fault her for not knowing and contaminating people, but I got angry after reading that she went and broke the one rule she was suppose to keep. It made me mad because she knew at that point that she couldn’t have been anywhere near food or handling food in public, but she still went and did. I am glad that she got locked up again on that island.

  • Rylie Kieny

    This was interesting as I knew very little surrounding this topic. In the start I was angry for the health department for stripping Mary away from her family however after she broke the only rule she had I no longer felt bad. She knowingly went back to cooking and infecting many others. Although she numbered 50 play people infected it is unsure how many people those infected. Its scary that one outbreak can start from one person and effect many. I think this article clearly explained the story of Mary and the typhoid outbreak.

  • William Ward

    Towards the middle of the article, I began to feel sorry for Mary, but after breaking the one and only rule she was given and endangering anyone she serves quickly killed that remorse. I bet the peach ice cream was too absolutely to die for. Great article on a subject I was far from familiar with, good information and story.

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