Synopsis
Prevent malaria in travellers, recognise infection immediately after endemic exposure, obtain definitive parasite testing without delay, and deliver species- and severity-appropriate treatment safely.
- Malaria is transmitted by female Anopheles mosquitoes; P. falciparum causes most fatal imported disease, while P. vivax and P. ovale can relapse from dormant liver hypnozoites.
- Fever after malaria-risk travel, often with headache, myalgia, rigors or gastrointestinal symptoms, is the key trigger; a regular cycle is not required.
- First-line diagnosis is urgent expert thick and thin blood-film microscopy with parasite density; add a rapid diagnostic test, but never use it as the sole rule-out test.
- If initial films are negative but suspicion remains, repeat films 12 to 24 hours apart until three appropriately examined sets are negative, while reassessing for sepsis and other imported infections.
- Severe malaria requires intravenous artesunate 2.4 mg/kg at 0, 12 and 24 hours, then every 24 hours until oral treatment is possible, followed by a complete effective oral course under specialist direction.
- Uncomplicated falciparum malaria can be treated with artemether-lumefantrine: four 20/120 mg tablets at 0, 8, 24, 36, 48 and 60 hours with food containing fat, if the patient can absorb oral medicine.
- Prevention combines awareness, bite avoidance and itinerary-specific chemoprophylaxis; no tablet is completely protective, so post-travel fever still needs immediate testing.
- Malaria is notifiable in England; notify suspected or confirmed disease according to current jurisdictional rules and urgently alert health protection if UK acquisition is possible.
Key red flags
Any fever or systemic illness after travel to a malaria-risk area requires same-day malaria testing, even when prophylaxis was taken or another diagnosis appears plausible.
Confusion, seizure, prostration, shock, respiratory distress, pulmonary oedema, significant bleeding, haemoglobinuria, hypoglycaemia or acidosis indicates potentially severe malaria.
Acute kidney injury, severe anaemia, marked thrombocytopenia or jaundice accompanied by another organ abnormality requires urgent senior and specialist review.
Pregnancy, infancy, older age, asplenia and immune compromise lower the threshold for admission because complications can evolve before a large peripheral parasite count is visible.
A first negative blood film does not exclude malaria when exposure and illness fit; repeat expert microscopy while pursuing alternative diagnoses.
A patient unable to swallow or retain oral therapy needs parenteral treatment and monitored care rather than repeated oral doses.
Fever, sweats or rigors after time in a malaria-risk area is the cardinal trigger for urgent testing, regardless of prophylaxis use or elapsed months.
Confusion, agitation, drowsiness, seizure, abnormal posturing or coma in parasitaemia indicates cerebral malaria once alternative causes are addressed.
Investigation priorities
Detect parasites, identify species, quantify parasitaemia and provide a baseline for response.
Management branches
A patient is febrile or reports recent fever after travel to any malaria-risk area.
- Record precise countries, regions and dates, then send urgent thick and thin films plus a rapid diagnostic test through a laboratory able to report immediately.
- Perform ABCDE and check bedside glucose while obtaining FBC, renal and liver profiles, coagulation, gas and lactate; assess pregnancy and oral absorption.
- If initial testing is negative but suspicion persists, arrange repeat microscopy 12 to 24 hours apart until three sets are negative and actively investigate concurrent sepsis.
- Notify malaria under current national rules; if local acquisition, transfusion, transplant or needlestick transmission is plausible, contact health protection promptly.