The incubation period for typhoid or paratyphoid is 6-30 days. The initial symptoms of typhoid and paratyphoid fevers include the acute or gradual onset of abdominal pain and tenderness, fever, chills, sweating, headache, anorexia, weakness, cough, sore throat, dizziness, and myalgias. Fever develops slowly beginning as low grade and rising to temperatures of 102°F -104°F (39°C-40°C) by the fourth day. This usually progresses to a severe illness with bacteremia and high fever that may last for weeks. Hepatosplenomegaly is common. Some patients will develop a rash of erythematous papules on the trunk (rose spots), and some will suffer altered mental status. Bowel perforation can rarely be seen. Intestinal hemorrhage, meningitis, chondritis, cholecystitis, pyelonephritis, orchitis, typhoid hepatitis, pneumonia, localized abscesses, endocarditis, and myocarditis are also complications.
In the United States, 75% of cases occur in patients aged younger than 30. Untreated, typhoid fever carries a 10%-20% mortality rate. In 15%-20% of treated patients, there is relapse after 2 weeks.
Although typhoid fever is rare in the United States, 9 cases of typhoid fever were documented in California and Nevada between April and July of 2010, with 7 of the patients requiring hospitalization. The US Centers for Disease Control and Prevention (CDC) linked the majority of cases to the consumption of frozen mamey (also called "zapote" or "sapote"), a tropical fruit pulp product used in milkshakes and smoothies.
The CDC has classified drug-resistant nontyphoidal Salmonella and drug-resistant Salmonella serotype typhi as serious concerns. They note that 67% of S. typhi are drug-resistant.
See Salmonellosis for discussion of serotypes Salmonella typhimurium and Salmonella enteritidis.
A01.00 – Typhoid fever, unspecified
4834000 – Typhoid fever
- In patients who have traveled to an area endemic for S. typhi and return with fever, also consider malaria. Other conditions that can mimic the illness include amebiasis, dengue fever, chikungunya, Zika virus infection, leishmaniasis (Old World, New World), leptospirosis, melioidosis, and trypanosomiasis.
- Acute bacterial gastroenteritis (Campylobacter, Shigella, Escherichia coli O157:H7)
- Tuberculosis – Can present as a prolonged febrile illness; diarrhea (and dysentery) is not expected.
- Endemic typhus – May be difficult to distinguish from typhoid fever.
- Bacterial abscess – Can present as a prolonged febrile illness.
- Endocarditis – Can present as a prolonged febrile illness.
- Q fever