Typhoid Mary and the Ethics of Epidemiology

What do we do when super-spreaders ignore facts?

Photo by Atoms on Unsplash

By now we all know the tragic tale of Mary Mallon and the collateral damage she wrought. But her case remains relevant especially in an era of super-spreaders who insist their personal liberties are more important than public health.

Mary Mallon was born in Ireland in 1869. She immigrated to the United States in about 1884 and swiftly found employment as a cook. She was particularly well known for her peaches and cream ice cream made by hand with fresh fruit. At first, the deaths and illness which surrounded her were considered tragic happenstance. George Soper — who had set to work trying to find the vector of the typhoid infections — initially suspected freshwater clams.

But, increasingly, as each potential vector proved negative and death and illness trailed behind Mary Mallon, Soper began to suspect the culprit was Mallon herself. He asked to sample her urine and faeces so that he could test for the pathogen and was — somewhat predictably — chased off by an enraged and carving fork wielding Mary.

Dr. Sara Josephine Baker, whose career really deserves its own article, was then enlisted to try to convince Mallon to consent to blood, urine, and faecal testing. It did not go well. Dr. Baker recounts that Mallon steadfastly refused the tests and then when compelled and facing arrest, tried to attack Dr. Baker and the police officers she had brought to protect and aide her.

This image, one of the best known for Mary Mallon was printed in The New York American (1909). Mallon certainly knew of her nickname as well as cartoons and public denouncements of her as she complained of these in a letter to her lawyer.

Mallon’s faeces tested positive for Salmonella typhi and she was subsequently detained in a cottage on the grounds of Riverside Hospital on North Brother Island. Over the course of two years she underwent routine tests for which she usually tested positive, but never exhibited any symptoms. She was given treatments all of which failed but refused the offer to have her gallbladder — where the bacteria was suspected to be residing in her system — removed.

In 1910 a new health commissioner released Mallon on the condition that she not work as a cook and check in regularly. She agreed to these conditions but did not comply with them. Mary Mallon was quickly employed under the alias Mary Brown once again as a cook, and once again she began infecting those who consumed foods like ice cream which she had prepared without cooking.

Mallon was again arrested and quarantined permanently in the cottage on North Brother Island where she died from complications from a stroke in 1938 at the age of 69.

There are basically two ways of looking at Mallon’s case.

Mallon, due in large part to her profession and the failure of public officials to educate her on her status as a healthy carrier ended up becoming a super-spreader of Typhoid Fever. At this point there was not effective treatment or inoculation for the disease and it killed about 10% of those infected. (Notably, William Henry Harrison is suspected to have died of Typhoid Fever contracted from contaminated water in the White House and thereby marking his term in office as the shortest ever at 31 days.) Her refusal to allow herself to be tested and her reticence to submit to quarantine and then the conditions of her release likely resulted in the deaths and illnesses of possibly hundreds to thousands of New Yorkers.

That said, Mallon apparently never was given up to date and comprehensive information on her own infection. She was handled — albeit largely due to her own actions — in an adversarial manner and she was forced to quarantine against her will. It also turns out Mallon was not the only healthy carrier of Salmonella typhi, but she was the only one quarantined against her will. Lastly, Mallon was Irish at a time when there was a fair amount of anti-Irish bigotry.

This was before ethics in medicine was really a thing and even the idea of public health was in its nascence. The aforementioned Dr. Baker pioneered public health and while she was revolutionary in her field some of her methods — such as administering smallpox vaccines to unconscious and drunk people — were questionable at best. Public hygiene and even the relationship between personal hygiene and health was not fully articulated. Additionally, Mary Mallon was the first confirmed “healthy carrier,” or individual infected with a pathogen but suffering no symptoms.

Horrific revelations on twitter regarding apparently unwashed white people aside, most people know to wash their hands after they go to the bathroom especially if they’ve pooped. It is also notable that Mallon was carrying the bacteria in her gallbladder and it usually only showed up in her faeces. The problem is even with modern anti-bacterial soap thoroughly washing your hands and killing all the microbes on them is quite difficult. Mallon would have been contending with turn of the century soap and harsh scrub brushes. Even if she were exceptionally hygienic there was only so much she could do.

The officials and doctors working with Mallon absolutely failed her. They did not give her reasonable explanations or information, their condition that she not work as a cook was not accompanied by any form of retraining or compensation for lost wages, and their ultimate solution — that she have her gallbladder removed — was at this point in history still rife with risk. Mallon felt fine and was not ever given a thorough and reasonable explanation for how and why the Typhoid infections were being traced back to her. She was strong, healthy, and probably saw a surgery as an unnecessary and silly risk for her to take.

But the fact of the matter was every time Mary Mallon went to pursue her dreams of supporting herself through cooking she infected more and more people with Typhoid fever. Ultimately, the handling of her case was unethical, but so was her own behaviour. She is responsible for multiple outbreaks, many illnesses, and a few deaths.

One of my first articles on Medium was about the importance of vaccines and public health measures. It’s quite lengthy, but it includes court cases, a bit of law and it is — for this type of publication — really well cited. I wrote it almost two full years ago and therefore well before the pandemic, but even so it includes an entire section on why people try to avoid things like vaccination which are super safe and can save not only your life but that of your neighbour.

There may be better case law out there, but Jacobson v. Massachusetts established (in 1905, no less) that the state can compel vaccination for the public good. But, that’s vaccination. Typically people are not so reckless that they’re willing to risk one another’s lives over refusing to wear masks or self-isolate. Or so I thought prior to 2020. But while the state or states may be able to compel vaccination it is a bit harder to legally enforce even hygienic actions for the public good.

In the normal course of medicine it’s quite good that the state or doctors can’t compel you to undergo treatment for something. In general you’ll probably want to, but it really should be your decision and this is — generally speaking — a matter of personal rights and freedoms. You have the right and freedom to determine how your health is managed. This is why I go jogging despite the fact that I absolutely loathe jogging.

However, in the case of infectious disease rapidly turning into an epidemic or, as is the case now, pandemic, your individual rights and freedoms do need to be balanced with those of the public good. You have a right to influence your own health outcomes, but you do not have a right to put others in danger.

Infectious disease is a bit annoying in that it does not always present as you might expect. Depending on who gets it it does not even behave as you might expect. One person might die from it where another might not even know they’ve been infected. Most of the time there are factors that influence levels of morbidity and mortality relative to infection, but sometimes it can be a bit of a wild card and because you cannot constantly test everyone for everything you will not immediately know the vector for disease transmission.

Stephen Colbert raising the alarm re: our ursine nemeses. (Comedy Central)

Living in a society means that you reap a lot of benefits like lights, roads, fewer bears, easily accessible food, and emergency services in case of bears. It also means behaving in a way that does not endanger those around you. If your house catches fire you wouldn’t just shrug and peace out. You certainly wouldn’t throw a flaming bottle of booze through your neighbour’s window. Either of these options are incredibly dumb and one is definitely a crime. So in a time with a highly contagious, deadly, and airborne pathogen making the rounds it’s just weird that some people are so insistent on not wearing masks and engaging in group activities.

Mary Mallon infected possibly hundreds of people. But she had to cook to do so. And she was never properly informed of exactly what sort of impact she was having and why. Also, for her to stop infecting people she had to either take a dramatic pay cut or have her gallbladder removed.

Mary Mallon’s modern counterparts are infecting more people just by being out in public breathing and touching things. But they are absolutely informed, they do know what they’re doing, and slowing the spread involves the incredibly simple act of wearing a mask and not going to or throwing big parties. No one wants your gallbladder, Karen; we just want you to not sloppy kiss all the cousins this year.

Unfortunately, and in a weird conspiracy twist that seems somewhere between Orwellian and Lovecraftian to me masks, vaccines, and public health have somehow become politicized. I’ve been trying to work out exactly how that happened and I do not have a simple answer. To be honest, I’m not even sure I have an answer.

But what I can say is while Americans especially explicitly rejected anti-public health measures at the polls and indicated democratically that they do want to see an end to this pandemic. Even so, elections only require a majority of votes and sometimes they only even require a plurality. While the 2020 election was a reasonably substantial majority, it was not a landslide and public health does require virtually everyone to adhere to reasonable actions and behaviours.

As I said in my lengthy vaccine article, herd immunity for highly contagious diseases requires about 95% immunity. Vaccinating 95% of the population is actually a huge undertaking. It’s a bit easier when you’re doing it as part of health check ups, but in this case the entire population needs to be vaccinated as quickly as the vaccine can be produced. And until that happens to stem the spread of the disease at least 95% of the population have to wear masks, self-isolate, practice social distance, and clean and sterilize surfaces. Realistically speaking, this is not going to happen.

Mary Mallon probably did not entirely deserve the misfortune which ruled her life. Her options were bad and there was not real support or sympathy for her at the time. She was a victim of bigotry and there could have been better outcomes in her case and for the public health in New York at the time. But with that said her rights at no point were more valuable than the lives of those infected. This is something I wish people would remember in a time of pandemic. Masks may obscure and smudge your perfectly applied lipstick, but take the hit. It’s better than killing someone.

And miss me with the, “I can’t breathe in a mask.” I’m autistic AND asthmatic and I do just fine.

Doctor of Palaeopathology, rage-prone optimist, stealth berserker, opera enthusiast, and insatiable consumer of academic journals.

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