The symptoms of typhoid fever usually develop 1 or 2 weeks after a person becomes infected with the Salmonella typhi bacteria.

With treatment, the symptoms of typhoid fever should quickly improve within 3 to 5 days.

If typhoid fever isn't treated, it'll usually get worse over the course of a few weeks, and there's a significant risk of life-threatening complications developing.

Without treatment, it can take weeks – or even months – to fully recover, and symptoms can return.

The main symptoms of typhoid fever are:

• a persistent high temperature that gradually increases each day
• a headache
• general aches and pains
• extreme tiredness (fatigue)
• a cough
• constipation

Later, as the infection progresses you may lose your appetite, feel sick and have a tummy ache and diarrhoea. Some people may develop a rash.

See your GP as soon as possible if you have symptoms of typhoid fever (even if you have been vaccinated against it), particularly if you have recently returned from travelling abroad.

It's unlikely that your symptoms will be caused by typhoid fever, but it's best to get them checked out in case you need treatment.

If you become ill while travelling abroad, you can get help by:

• contacting a representative of the travel company you booked with
• contacting your travel insurer
• contacting the British consulate in the area you're visiting or, if you're feeling very ill, the local emergency services

The Foreign & Commonwealth Office (FCO) provides travel advice by country, and the contact details of all the British consulates and embassies in foreign countries can be found on GOV.UK.

Before you travel, it's a good idea to make a list of relevant contact details and telephone numbers in case of an emergency.