The febrile returning traveller: a case-based approach

The case

A previously well adult returns to the UK after four weeks visiting family in West Africa. Ten days after landing they develop shivering, headache, aching muscles and a high temperature that comes and goes. They took some malaria prevention tablets but admit they missed several doses and stopped early. There is no cough or rash. At first they assumed it was flu, but the fevers keep returning and they feel increasingly drained. This picture — fever after travel to a malaria area, with imperfect prevention — is exactly the situation where a clinician must think of malaria first and act quickly, because early malaria can look deceptively like a simple viral illness.

Why malaria comes first

Malaria is a medical emergency. It is caused by a parasite spread by mosquito bites, and the most dangerous type, Plasmodium falciparum, can progress from mild-seeming fever to organ failure within hours to days. Most UK malaria cases occur in people returning from Africa, and symptoms usually begin within a few weeks of travel — but can appear months later. There is no symptom pattern reliable enough to rule malaria out at the bedside; the classic cyclical fever is often absent. That is why the rule in UK practice is simple: anyone with fever who has visited a malaria area needs an urgent malaria blood test, whatever else might also be going on.

How it is tested and treated

Diagnosis relies on a blood test. A blood film examined under a microscope, often alongside a rapid antigen test, confirms whether parasites are present and which type. Because early films can be negative, guidance is to repeat the test over three days if the first is clear but suspicion remains. Confirmed malaria is treated in hospital with antimalarial medicines chosen according to the parasite type and severity; falciparum malaria, or anyone who is very unwell, is usually admitted. Treatment is effective when started early, which is the whole point of testing fast. Other travel infections — such as typhoid, dengue or a liver abscess — are considered too, but never at the expense of excluding malaria first.

The wider assessment

Beyond malaria, a good travel history shapes the search. Clinicians ask where exactly you went, what you did, what you ate and drank, insect and freshwater exposure, contact with unwell people, animal or needle contact, and vaccinations taken. The timing of the fever after travel narrows the possibilities. Examination looks for a rash, jaundice, an enlarged spleen or liver, and signs of serious illness such as confusion or low blood pressure. Basic blood tests, urine and sometimes chest imaging help build the picture. The aim is to identify anything dangerous or contagious quickly while treating the person in front of you, not just chasing a single diagnosis.

Red flags and safe follow-up

Some features demand immediate hospital assessment: drowsiness or confusion, difficulty breathing, a fever that will not settle, reduced urine, yellowing of the skin or eyes, bruising or bleeding, a widespread rash, or simply feeling rapidly worse. In a returning traveller these can signal severe malaria or another serious infection. Even without them, fever after travel to a malaria area should never be watched at home in the hope it passes. The safe path is to be seen and tested promptly. If the first tests are reassuring but symptoms continue, arranging repeat testing and clear advice on when to return closes the safety net.