Typhoid fever

Typhoid fever is a bacterial infection that has become rare in industrialized countries, but that is still common in countries with poor hygiene routine where it is responsible for up to 20 million estimated cases and up to 161,000 deaths each year.(1)

Symptoms of typhoid fever

  • Following a 5 to 21-day incubation period, typical signs, including diffuse abdominal pain, headache, prolonged fever, anorexia, nausea, loss of appetite, and constipation or sometimes diarrhea, progressively appear.(2)
  • Daytime drowsiness and nighttime insomnia are characteristic signs.
  • Possible complications include gastrointestinal hemorrhage and perforation, heart failure, and encephalitis.
  • Effective antibiotics are available, and the prognosis in patients under treatment is usually favorable.
    Nevertheless, recovery may be followed by chronic carriage during several months. Moreover, the emergence of drug-resistant strains makes the treatment more complex.

Epidemiology and vaccination against typhoid fever

  • The reservoir of the pathogen is strictly human.
  • Transmission usually occurs through the fecal-oral route by ingestion of contaminated food or water.
  • Prevention relies on good hygiene and vaccination.
  • Several vaccines against typhoid fever are available.


1 - WHO. Typhoid Fact sheet. Updated January 2018, accessed January 2018. http://www.who.int/mediacentre/factsheets/typhoid/en/

2 - WHO. Typhoid Fever vaccines position paper; WER 2008, 83: 49-60. Accessed January 2018. http://www.who.int/wer/2008/wer8306.pdf?ua=1

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