Typhoid Mary Was the Original Super Spreader

Typhoid  Mary
Mary Mallon, aka "Typhoid Mary," (seen here hospitalized on Brother Island) was an asymptomatic carrier of typhoid fever who spread the disease throughout New York in the early 20th century. Bettmann/Fotosearch/Getty Images/HowStuffWorks

Typhoid fever isn't­ a p­retty disease. Painful diarrhea, high fever, lethargy, nasty red rashes, sleeplessness, headaches and coughing are typical symptoms of the illness. Left untreated, typhoid fever can result in death. Typhoid fever is caused by Salmonella serotype Typhi, the parasite that spreads through water and food, making the disease highly contagious.

That was the case in turn-of-the-century New York City. Typhoid fever was a growing problem. The Department of Health had a lot on its plate; in addition to typhoid, it was trying to quell out­breaks of smallpox, tuberculosis, diphtheria and whooping cough that were also sweeping through the area. Luckily, scientists had developed a sophisticated understanding of microbial diseases and how they spread — even though most of the public didn't quite grasp all of it yet.


The Department of Health knew what caused typhoid, but dealing with the spread of the disease was another question altogether. It's something we are dealing with today in our attempt to quell the spread of coronavirus. We can't simply cast away those who are contagious to fend for themselves. So authorities must walk the line between keeping societies safe from debilitating illness and infringing on the personal rights of those who are sick. This same controversy reached a fever pitch in early 20th-century New York when it came to one individual: Mary Mallon, aka Typhoid Mary.

It might surprise you to learn that Mallon was actually immune to typhoid fever. Though it's uncommon, some people like Mallon are asymptomatic carriers. That means they can carry and spread the parasite but never have any symptoms. But even worse, Mallon was in a disastrous occupation for a carrier of typhoid fever: She was a cook.


Who Was Mary Mallon?

Typhoid  Mary
Mary Mallon had at least 120 out of 163 stool samples test positive for Salmonella serotype Typhi. New York County Clerk Archives

­Mary Mallon was born in Ireland in 1869. When she was a young teenager, she left for New York City, where she lived with her aunt and uncle until their death. Despite being alone in a large metropolis in a new country, Mallon earned a good living as a servant in various households. By her 30s, she was cook serving a dessert of ice cream and peaches that was to die for (quite literally, as we'll see).

In 1906, Charles Henry Warren, a wealthy banker, rented a home in the upscale Oyster Bay community. Six of the 11 in the home came down with typhoid fever, but survived. The Nassau County Department of Health investigated the outbreak, but couldn't find a cause. Dr. George A. Soper, an epidemiologist and sanitation engineer, was called in to investigate. Soper was well-versed in the disease and aware of cases involving immune carriers.


Soper had determined the outbreak was caused by a person and not from food. He focused his attention on Mallon, who began working for the family just weeks before the first person fell ill. After investigating Mallon's work history from 1900 to 1907, he found 22 other wealthy New York families Mallon had worked for in their summer homes — and 22 of them had become infected with typhoid. Perhaps she had used the bathroom without washing her hands and then prepared food for the families. If so, she may have spread the disease.

Soper learned that most of the food Mallon served was cooked, and therefore most likely safe from the salmonella that caused typhoid fever. But Mallon's trademark ice cream and peaches dessert could have very likely infected the families.

Soper was desperate to find Mallon, and it took him four months to track her down. He found the tough Irish cook working in a Park Avenue brownstone and when he explained that she was likely infecting people with typhoid fever, and that he needed samples of her feces and urine to confirm, she lunged at Soper with a carving fork.

Nevertheless, Soper was determined to test her for the illness, even if he had to drag her away kicking and screaming — which was exactly what happened.


Typhoid Mary vs. New York City

Typhoid Mary
Mary Mallon lived out the rest of her life quarantined in this one-room cottage on North Brother Island located in New York City's East River. New York City Department of Records

Realizing that Mallon wasn't going to give up easily, Soper went to New York's Department of Health with his evidence and quickly convinced officials to dispatch an inspector, an ambulance and several policemen to bring her in. Eventually she was arrested and placed under quarantine in a cottage at Riverside Hospital on North Brother Island off of Manhattan. Finally, Mallon was escorted to the hospital where she tested positive as a carrier for Salmonella typhi, the bacteria that causes typhoid. That was in 1907. About 3,000 New Yorkers were infected by Salmonella typhi that year, and Mallon was the main reason for the outbreak.

The press latched on to the story and dubbed her "Typhoid Mary." While some people were outraged at what they perceived as a violation of Mallon's civil liberties, the newspapers mostly painted her as a menace to society. One illustration depicted her breaking egg-sized skulls into a skillet.


In 1909, Mallon sued the New York Department of Health, though she lost her case. No one ever explained to her what the significance of being a "carrier" meant. In 1910, a new health commissioner freed Mallon and from quarantine under the condition she never work again as a cook. She was eventually released but went straight back to the only work she knew: cooking. And in many different spots across New York and New Jersey, including as a cook in a hotel, a Broadway restaurant, a spa, and a boarding house, again threatening public health.

In 1915, another typhoid outbreak occurred at Sloane Maternity Hospital, and Soper was again called in to investigate. Guess who the cook was? Typhoid Mary. Mallon was sent back to North Brother island — this time for good. She remained on the island until her death, 26 years later.