Typhoid Fever, Case Study Example

  1. Typhoid fever is an illness that is caused by a bacterium: Salmonella Typhii.

Typhoid fever is associated with the following symptoms and signs:

  • Fever; fever is a constant symptom that is associated with the fever that increases in intensity over time
  • Headache
  • Weakness and fatigue
  • Cough
  • Loss of appetite
  • Abdominal pain
  • Diarrhea or constipation
  1. What is the annual incidence of typhoid fever in the US?

According to the CDC, there are roughly 400 cases of typhoid fever annually.

  1. What was the mechanism of disease transmission between Mary Mallon and those who became ill?

Contaminated food was the mechanism of disease transmission from Mary Mallon to other individuals.  Mary had typhoid fever; when preparing food, without proper disinfectant, she then passed on the fever to other individuals.

  1. How would you describe the epidemiology triangle in Mary’s case?

The epidemiological triangle consists of three different components: host, agent, environment. The host in this example is Mary- she was the host of typhoid fever.  The agent in this case is the bacteria that carried typhoid fever.  The environment is food that was prepared by Mary.

  1. What strategies did the society of the early 1900s use to prevent Mary from spreading the disease?

The main strategy in the 1900s was to isolate the person in a distant place (away from people) so that the infection could not be spread.

  1. What disease prevention strategies would be used today?

The typical prevention strategies used today are: washing hands, sterilization, and screening.

  1. After learning about Mary Mallon what is your position on a policy to screen food handlers for infectious diseases such as Typhoid Fever and Hepatitis A, which can be spread by food?

I support the policy; although the policy would not necessarily prevent any and all outbreaks of the bacteria, it would be a good step in the direction of preventing potential cases.



CDC, Typhoid Fever Facts.  Available at CDC web site: www.cdc.org