Typhoid fever is caused by Salmonella typhi bacteria. It can also be caused by Salmonella paratyphi, a related bacterium that usually leads to a less severe illness. In countries such as the Philippines, typhoid fever remains a serious health threat, especially for children.


  • If you ingest bacteria in contaminated food or water (patients with acute illness can contaminate the surrounding water supply through stool and, in turn, taint the food supply).

Risk Factors

  • If you live, work in or travel to areas where typhoid fever is endemic (India, Southeast Asia, Africa, South America)
  • Work as a clinical microbiologist handling Salmonella typhi bacteria
  • Have close contact with someone who is infected or has recently been infected with typhoid fever
  • Have an immune system weakened by medications such as corticosteroids or diseases such as HIV/AIDS
  • Drink water contaminated by sewage that contains S. typhi

Signs and Symptoms

The incubation period is usually one to two weeks, and the duration of the illness is about four to six weeks. Patients usually will experience:

  • sustained fever as high as 103 F-104 F (39 C-40 C)
  • chest congestion
  • poor appetite
  • abdominal pain
  • headaches
  • generalized aches and pains
  • lethargy (usually only if untreated)
  • intestinal bleeding or perforation (after two to three weeks of the disease)
  • diarrhea or constipation


  • Vaccination
  • Wash your hands
  • Do not drink untreated water
  • Avoid raw fruits and vegetables
  • Do not eat street food

Vaccines available to prevent Typhoid fever:

Typhoid Vaccines

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