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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

  • Madison Downing

    I really don’t know how I feel about Mary Mallon because even though she didn’t mean it she still hurt a lot of people. And even after she changed the rules for people who were survivors of typhoid fever she then went back to cooking and affecting more people causing the death of two other people on top of the 3 from the summer home. Also putting people on an island to kept them away from society seems understandable to a point if it was designed better than just moving them away from everything they have ever known, it must have been so lonely and terrifying. This story of Typhoid Mary was very educational, life-changing, and heart-breaking because at the end of the day, a woman couldn’t do what she loved, to cook for people and make them happy.

  • Nathalie Herrera

    I had never heard the full story of “Typhoid Mary.” It was interesting to read how she was isolated from society by being placed on an island with other infected people who she was immune to, but did this in order to not spread disease. Although, I was glad to see in the end she was still able to see her family and friends but supervised. Very interesting read!

  • Michael Hinojosa

    The name Typhoid Mary was one I only briefly heard of in my history classes in not only middle school but high school as well. While the discussions of her weren’t very long and only went over how she unknowingly infected people with her cooking they were still interesting enough to peak my interest with this article and frankly I’m glad it did! I never knew the actual backstory on Mary nor did I know of her real name so this was a nice summary of her history!

  • Sienna Guerra

    I have always heard the phrase “Thyroid Mary” but never knew the context behind it. Mary Mallon is such a savage by knowing that she could not break her agreement of being a cook again yet infected 25 people that had to hospitalized and led to the death of two. As she did cook food for the hospital, she was sentenced to be isolated from society for the bacteria infection. It is both sad and crazy that she put so many life’s in dangers all because of the food that they ate.

  • Daniela Cardona

    Upon clicking on this article, I did not think I knew anything about the topic. As I read a little more and saw the name “Typhoid Mary,” I immediately knew it sounded familiar. I knew I had heard the name, but the specifics I wasn’t sure about. I appreciated that through this article I really felt I got the whole history of who Typhoid Mary was. On top of that I got a brief history on the disease itself and how it affected the country many years back which was really interesting. I appreciated how Mary stood up for her rights and fought for a chance to live in society despite her unfair punishment. Although it backfired greatly, I also appreciate she persisted to do what she loved despite mandates. However, I do still believe it was in poor judgement as she got more people sick.

  • Enrique Segovia

    This article expanded my knowledge about “Typhoid Mary”, an infamous name recognized throughout disease-fearing Americans. I had previously read an article back in high school about Mary Millon and her mysterious, yet problematic condition. However, in this article I read in my Food Science course, she did not cooperate with the health agencies but instead continued to run off and she refused to get her bladder removed, since the persecutors speculated that was the source of infection. She was a carrier, but she was not infected with the typhoid fever; there are many cases where people are infected and have no clue that they are the source of infection. Hence, this particular case helped researchers, such as George Soper understand better the science behind carriers and diseases.

  • Peter Coons

    Though Typhoid Mary took many lives due to her status, part of me thinks that it is a good thing that her spree of killings was found to be possible by food contamination. As someone who has worked in the food industry, no single event is more feared than the health inspection, and with good reason. A place serving people food should be subject to the upmost scrutiny, and any failure in that regard should be made public to protect the public. The revolution in public safety ignited by this case is something we should all keep in mind when considering buying from that food truck with a “C-” rating.

  • Crystal Baeza

    It’s such a shame Mallon had to live with a disease she had no idea she had from the beginning. I’m sure she didn’t have bad intentions to cause such an ugly illness to the people she loved cooking for. Although, I agree it was her right to sue being isolated from her family and be put on some island but don’t understand why didn’t she follow the rules to stay out. She knew her cooking could cause major problem for those eating her food so why did she continue doing so? I’m glad she was put back on the island and was supervised at all times. I pity her but at the same time believe she received what she deserved.

  • Luke Lopez

    Mary Mallon lived a tragic life in the way that she was sentenced to an island and was isolated from society, because of a bacteria infection that she did not want. Mallon, even though she knew of her agreement to never become a cook again, broke that agreement and infected twenty-five people and killed two people in a hospital because she was a cook for a hospital. She should not have became a cook again, because she knew that she was putting people’s lives in dangers by cooking for people.

  • Pedro Gonzalez Aboyte

    Before reading this article, I had heard of “Typhoid Mary” but I never knew the story behind it. This article does a great job of illustrating everything she had to go through and how she had to deal with consequences for decisions she decided to make. Mary Mallon was always passionate about cooking and due to the circumstances, she had to strip herself away from it. This was hard, obviously, as she had to give it up in order to live in society but she couldn’t resist and was forced to move back to the island. This was a very good and detailed read.

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