New York City, 1901 – an upper-class family presented with fevers and diarrhoea, diagnosed with the infection typhoid fever. This was unusual as typhoid fever was classically associated with poor hygiene, overcrowding and lower socioeconomic status households. It was atypical to see typhoid fever in upper-class households. Within a year, a lawyer and his household fell ill to the same disease – 7 out of 8 people contracted typhoid. Another case emerged 5 years later in Long Island, New York – an area where typhoid fever was very uncommon. This time, 10 out of 11 family members were hospitalised with typhoid. Countless families fell victim to typhoid fever within this year and people started becoming curious as to the cause of this epidemic.
In 1906, typhoid researcher George Soper began investigating the epidemic and found a common link between all of the families who became sick. They had all at some point employed a cook by the name of Mary Mallon. Soper noticed that Mallon had worked for each of these families roughly three weeks before each of them fell victim to the illness, upon which she would leave the job for another family. Soper approached Mallon to obtain urine and stool samples to prove this, but Mallon adamantly refused and denied any responsibility in her possible role in spreading typhoid as she “was not sick”.
Eventually, the New York City Health Department appointed Dr Sara Josephine Baker to handle the situation. Mallon still refused to comply with the investigation and had to be taken into custody by the police. She was forced to be tested while in prison, which proved that she was an asymptomatic carrier of typhoid fever. Doctors discovered that she had a significant growth of typhoid bacteria in her gallbladder. It was determined that Mallon has infected the families through preparing and serving food (she was famous for her ice cream) with poor hand hygiene.
Due to her non-compliance to the order of restricting her from being a cook, Mallon was quarantined for the rest of her life until she died from a stroke in 1938. Mallon – or as the media called her, “Typhoid Mary” – was the source of at least 51 confirmed typhoid fever cases, three of which were fatal. Some estimates say she could have been responsible for as many as 50 deaths as she had worked under many aliases. All because she did not wash her hands properly.