You should see your GP if you think you have typhoid fever, particularly if you have recently returned from travelling abroad.
Your GP will want to know whether you have travelled to parts of the world where the infection is present, or whether you have been in close contact with someone who's travelled to these areas.
Typhoid fever is most common in the Indian subcontinent, Africa, southeast Asia and South America.
A diagnosis of typhoid fever can usually be confirmed by analysing samples of blood, poo (stools) or pee (urine).
These will be examined under a microscope for the Salmonella typhi bacteria that cause the condition.
The bacteria aren't always detected the first time, so you may need to have a series of tests.
Testing a sample of bone marrow is a more accurate way of diagnosing typhoid fever.
But getting the sample is both time-consuming and painful, so it's usually only used if other tests are inconclusive.
If typhoid fever is confirmed, other members of your household may also need to be tested in case you have passed the infection on to them.