Typhoid fever is an illness caused by the gram negative bacteria salmonella typhi. Spread is faeco-oral and it is endemic in many developing countries.
Usual incubation period is 7 to 14 days (range 30 to 60)
Symptoms and signs include:
- fever (95%)
- anorexia (70%)
- hepatomegaly (40%)
- vomiting (40%)
- abdominal pain (30%)
- diarrhoea
- initial constipation
- headache
- splenomegaly
Complications include
- encephalitis
- GI bleeds
- intestinal perforation
Risk of severe illness is greater in those who are immunicompromised or who have decreased gastric acid (eg on PPIs)
Diagnosis: gold standard is blood culture; the Widal test is no longer recommended due to low specificity and sensititivity. Urine and stool cultures may be positive from the second week of infection.
Treatment:
- ciprofloxacin, azithromycin or ceftriaxone
- rehydration
A vaccine is available.
Less than 1% of those treated die; untreated mortality is around 10%.
