What Is Salmonella Typhi?

Salmonella typhi is the bacteria that causes typhoid fever, an illness initially characterized by high fever, stomach pains, weakness and a rash with rose-colored spots. Severe symptoms include meningitis and delusions. People can carry or pass on the bacteria while showing no symptoms.

History

• Karl J. Erberth isolated the Salmonella typhi organism in 1880. The first vaccine against typhoid fever came 17 years later, in 1897, at the hands of Almroth Edward Wright. Scientists in 2001 deciphered Salmonella typhi's genetic code, prompting optimisim for the disease's eradication.

Geography

• Salmonella typhi affects up to 21.5 million people annually. About 400 cases occur in the United States, 75 percent of which are a result of international travel. Visitors to developing areas in Africa, Asia and Latin America are at highest risk.

Causes

• Salmonella typhi lives in the bloodstream and intestinal tract, and is spread via contaminated food or drinks. Salmonella typhi is common where sewage contaminates water. Symptoms emerge one to three weeks after exposure.

Treatment

• Death from infection occurs in less than 1 percent of cases in which antibiotic treatment is given. Ten to 20 percent of untreated cases end in death.

Random Facts

• Salmonella typhi only affects humans. Mary "Typhoid Mary" Mallon was the most famous carrier, having transmitted the bacteria to at least 50 people while healthy herself.