Typhoid Mary: Carrier of Salmonella typhi

Typhoid Mary: Carrier of Salmonella typhi

In 1869 girl named Mary Mallon born in Ireland. Mary emigrated to US in 1884, started working as a domestic help to the wealthy families and later became a cook. Mary was a healthy carrier of Salmonella typhi bacteria which is responsible for typhoid fever and killed many people unknowingly, later she stigmatized as 'Typhoid Mary'. Before going to further details about 'typhoid Mary' first know what is typhoid fever.

What is Typhoid fever

Typhoid fever is a serious enteric fever caused by bacterium, Salmonella enterica, serovar typhi  also known as Salmonella typhi. It is a gram negative,unicellular, motile (flagella present all around the cell), facultative aerobes and non spore forming bacterium belongs to Enterobacteriaceae family.

Salmonella typhi under scanning electronic microscope

Salmonella typhi once enter into the body through mouth reach to intestinal cells and infect them, then it reach to blood cause septic form of infection and from blood it passes through lymphatic system and infect liver, spleen and kidneys . Toxins released by bacteria into the blood, upset thermal regulation and water-salt metabolism it may further affect arterial pressure.

Source of Infection

Sources of infection are food and drink contaminated with human or animal excreta containing Salmonella. The following sources are important:

1. Water contaminated with feces

2. Contaminated milk and dairy products with improper handling and unpasteurization.

3. Seafood from contaminated water body.

4. Raw or under cooked meat and meat products from infected animals.

Illustration of Typhoid source of infection

Symptoms of typhoid 

Once bacteria enter into the body after 7-14 days symptoms start to appear which are shown in the figure below:

Carrier of typhoid

After manifest or sub-clinical infection, some individuals continue to harbor Salmonella in their tissues for variable length of time (i.e. convalescent carriers or healthy permanent carriers). Permanent carrier harbor the Salmonella in the gall bladder, biliary duct or rarely in the intestine or urinary tract.

Mary Mallon was a healthy carrier of salmonella, her gall bladder was harboring the organism. In 1906 she was working as a cook in Charles Henry Warren a wealthy New York banker's household. During August 27 to September 3, 6 of 11 people diagnosed with typhoid from his house. Initially it was believed that fresh water clams could be the reason behind the infection. But who did not consume the clams were also among the infected. Later conducted interrogation of the sick people and other individuals present in the house revealed, that Mary was also suffering from moderate form of typhoid with no signified symptoms. 

George Sober a sanitary engineer hired by warren's family was behind these finding. He started stalking Mary and attempted to collect her feces, urine and blood samples. He found out that Mary served in 8 families previously and 7 of them experienced typhoid and 22 people were died due to the disease. Immunization against Salmonella was not developed until 1911. People were under threat, Mary had to be restrained. New York department of health sent doctor to bring Mary for check up but she was uncooperative and had to be forced to give samples. Her stool was positive with Salmonella typi thus sent to isolated place called Northern brother's island. She was quarantined in the cottage there. 

Northern Brother's Island

During her two years of confinement she was unsuccessfully treated and was even offered to remove her gall bladder but she denied. 

Mary Mallon in Riverside hospital, Northern Brother's Island

In 1910 new health commissioner of New York freed Mary and helped her to find new employment but not as a cook but other domestic help. She started working as laundry woman but her salary was low, soon after she again managed to obtain cook's job in Solane Maternity Hospital, Manhattan but with the fake name 'Mary Brown'. 

In three months she infected around 25 people of the hospital staff, she again sent back to Northern Brother's Island and remained there until her death. She labelled as 'Typhoid Mary'.  In 1932 she had a stroke of apoplexy which made her bed ridden. After 6 years she died.

Mary Mallon during her exile in Northern Brother's Island

She died in November 1938 and buried in grave at St. Raymond's cemetery, Bronx. According to Postmortem report she was shedding Salmonella typhi from her gall bladder and was a potent source of typhoid.

Mary Marllon  grave at St. Raymond'S Cemetery

Prevention & Treatment

Taking preventive measures one can avoid infection

1. Wash your hand

2. Avoid drinking untreated water

3. Avoid raw food and vegetables

4. Consume hot properly cooked food

There are many antibiotics and vaccines available for typhoid
Ciprofloxacin is effective antibiotic against typhoid. Before going to high risk areas getting vaccinated is recommended.

Thank you for reading

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