Typhoid fever is a potentially life-threatening bacterial illness that occurs when people consume foods or fluids contaminated with the bacteria Salmonella typhi. The bacteria quickly multiply in the body and spread from the intestines to the bloodstream. They may affect the liver, lymph nodes, spleen and gallbladder.

The incidence of typhoid fever has been dramatically reduced in industrialized nations due to improved sanitation. However, typhoid fever remains common in developing countries. People who travel to developing areas of the world are at an increased risk of infection. People living in communities with poor sanitation, or among people who practice poor hygiene (e.g., not washing hands after defecation or urination) are also at an increased risk of contracting a variety of infectious diseases, including typhoid fever.

Fever is the primary symptom associated with typhoid fever. A sustained fever typically runs as high as 103 to 104 degrees Fahrenheit (39 to 40 degrees Celsius). Some patients also develop distinctive rose spots on their chest or abdomen. Additional symptoms include headaches, loss of appetite and weakness. As the illness progresses, it may cause more severe symptoms, including delirium and hallucinations. Left untreated, typhoid fever can be fatal.

Blood or stool tests are typically used to identify the presence of Salmonella typhi bacteria. These tests may be performed after treatment to ensure no Salmonella typhi bacteria remain in the body. Antibiotics are typically used to treat typhoid fever.

People who travel to developing areas are urged to take precautions to prevent infection. This includes vaccination against typhoid fever. In addition, potentially contaminated foods and beverages should be avoided while traveling.