Introduction to typhoid and paratyphoid fevers
Typhoid and paratyphoid fevers (collectively known as enteric fever) are due to infection with Salmonella Typhi or1 Salmonella Paratyphi2 A, B or C, and are almost always acquired outside Australia. They are endemic in India, Pakistan, Bangladesh and, to a lesser extent, South-East Asia, Africa, South America and the Middle EastMarchello, 2020.
A patient with a history of recent travel to an endemic area might be suspected of having typhoid or paratyphoid fever based on their presentation alone or because a Salmonella species has been identified (but as yet untyped) in samples taken for blood culture.
The clinical presentation of typhoid and paratyphoid fevers can vary, but usually involves a gradual onset of fever that peaks after 1 week. Patients may also experience abdominal symptoms (eg diarrhoea, constipation, nausea, vomiting, abdominal pain) and have headache, cough or fatigue. Children younger than 5 years often present with fever alone, which can result in the diagnosis being missedBasnyat, 2021.
Conditions that often present with a nonspecific febrile illness in returned travellers, including dengue fever, malaria and rickettsial infections, should be considered as differential diagnoses.