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Typhoid and paratyphoid fever are caused by infection with the bacterium Salmonella enterica subspecies enterica serovar Typhi or Paratyphi. Humans are the only reservoirs of S. Typhi and S. Paratyphi.

Typhoid is spread when a person drinks or eats food and water contaminated by human waste (stool or urine) containing Salmonella Typhi bacteria. The organism is often shed in the stool by chronic carriers of the bacteria. Typhoid and paratyphoid fever are not endemic in the United States. Travelers to developing countries where exposure to contaminated food or drink is likely should be vaccinated against typhoid fever before travel.


Resources for the general public

Resources for health care professionals


Purpose of surveillance:

  • To identify and track chronic typhoid carriers to prevent transmission of the disease
  • To identify and eliminate sources of transmission, including contaminated food and water

Typhoid case data

Local epidemiology:

  • Seven confirmed and two probable cases of typhoid were reported in 2015; two of the cases occurred in children under 18 years of age. This is similar to the five-year average of ten cases per year. Four of the cases were hospitalized, and none died. Eight of the cases acquired their infection outside the United States in the 60 days prior to onset; seven reported travel to India and one to Samoa. The ninth case did not report travel, but was a household contact to a recent traveler to Cambodia who was suspected to have been a carrier.

  • Typhoid fever is endemic to many parts of Asia, Africa, the Caribbean, Central and South America. During 2015, there were also three cases of paratyphoid fever (type A) reported; one was under the age of 18. One case required hospitalization; none died.

  • Two of the cases had returned from recent travel to Asia (one China, one Southeast Asia).
    Each year in Washington state between four and 22 cases of typhoid fever and fewer than 10 cases of paratyphoid fever are reported.