Malaria

A fever after travel to a malaria area is malaria until proven otherwise. Falciparum malaria kills within days and is a same-day emergency.

What it is

A parasitic infection transmitted by mosquito bites, and the most important travel-related infection seen in the UK, with around 1,500 to 2,000 cases a year, almost all imported.

Plasmodium falciparum causes the great majority of severe disease and deaths. It can progress from feeling unwell to organ failure within 24 to 48 hours, which is why **any fever in somebody who has been to a malaria area in the previous year is a same-day emergency assessment**, and why a single negative blood film does not exclude it; three films over 48 hours are needed.

The largest group of UK cases is people visiting friends and relatives in their country of origin, who often do not take preventive tablets because they believe childhood exposure protects them. That immunity fades within a year or two of leaving, and it is the single most important preventive message.

Prevention is bite avoidance and antimalarial tablets appropriate to the destination, started before travel and continued afterwards for the full period. Stopping early is a common and dangerous mistake.

Vivax and ovale malaria can relapse months or years later from dormant liver stages, and need an additional drug to clear them.

There is no vaccine available for UK travellers.

Signs you might notice

Fever, often with sweats and shaking chills.

Headache, muscle aches, tiredness.

Nausea, vomiting, diarrhoea, abdominal pain.

Cough.

Symptoms can start from a week after exposure up to a year or more later.

**Same-day assessment for any fever within a year of travel to a malaria area.** Say where you have been and when.

999 or A and E for: confusion or drowsiness; seizures; difficulty breathing; vomiting everything; passing little urine; jaundice; or bleeding. These indicate severe malaria.

In a child, or in pregnancy, the threshold should be lower still; both deteriorate faster.

A negative test does not exclude it if symptoms continue; repeat testing is standard.

How it can affect day-to-day life

The prevention message that saves most lives in the UK is aimed at people visiting family abroad: previous immunity does not protect you now, children born here have none at all, and tablets are needed for the whole family.

Bite avoidance genuinely works: an insecticide-treated net, repellent containing DEET, covering up at dusk and dawn, and air conditioning where available.

Antimalarial tablets must be continued for the full period after returning, which for some drugs is four weeks. Stopping on the plane home is a classic error.

Travel clinics and pharmacies can advise on the right drug for the destination, and free NHS provision varies.

Anybody who has had malaria should mention it at any future illness with fever, particularly for vivax, which relapses.

Blood donation is deferred for a period after travel or infection.

Supporting someone well

Get any fever after travel assessed the same day, and say where you have been.

Take antimalarial tablets as prescribed, and complete the full course after returning.

Tell people visiting family abroad that previous immunity has gone and that children have none.

Use bite avoidance: treated nets, DEET repellent, covering up at dusk and dawn.

Get travel advice before booking, not the week before flying, since some drugs must start well in advance.

Do not accept one negative test if the fever continues; ask for repeat films.

Treat confusion, drowsiness or breathlessness as severe malaria and go to A and E.

Mention past malaria at any future febrile illness.

Where to get help

A GP practice or A and E the same day for fever after travel; 999 for severe features.

A travel clinic or pharmacy before travel for the correct antimalarial for the destination.

The NHS Fit for Travel and TravelHealthPro websites for country-specific advice.

UK Sepsis Trust for the overlapping warning signs of severe infection.