Typhoid fever is a bacterial infection characterized by diarrhea, systemic disease, and a rash -- most commonly caused by the bacteria Salmonella typhi (S. typhi).

The bacteria that causes typhoid fever -- S. typhi -- spreads through contaminated food, drink, or water. If you eat or drink something that is contaminated, the bacteria enters your body, and goes into your intestines, and then into your bloodstream, where it can travel to your lymph nodes, gallbladder, liver, spleen, and other parts of the body.

A few people can become carriers of S. typhi and continue to release the bacteria in their stools for years, spreading the disease.

Typhoid fever is common in developing countries, but fewer than 400 cases are reported in the U.S. each year. Most cases in the U.S. are brought in from overseas.