Malaria: The Complete Guide to Symptoms, Testing, Treatment and Prevention

Malaria still kills more than half a million people every year, most of them children under five. It is preventable and curable. This guide explains how to recognise it early, get the right test and treatment, and protect your family.

Imagine your four-year-old has had a fever since yesterday. You gave him leftover tablets from the last time and he seemed better this morning. Tonight he is shivering, vomiting and hard to wake. Malaria can move from mild to life-threatening in a day. Testing early and finishing the right treatment is what keeps a simple illness from becoming an emergency.

What is malaria?

Malaria is a life-threatening disease caused by Plasmodium parasites, spread to people through the bites of infected female Anopheles mosquitoes. Five species infect humans. Plasmodium falciparum causes most severe disease and deaths, particularly in sub-Saharan Africa. Plasmodium vivax is common in Asia and Latin America and can hide in the liver and cause relapses months later. P. ovale, P. malariae and P. knowlesi are less common.,After an infected bite, the parasites travel to the liver, multiply, and then invade red blood cells. The cycle of red cells bursting releases more parasites and causes the typical fevers and chills.

How big is the problem?

According to the World Health Organization’s World Malaria Report, there were an estimated 263 million malaria cases and around 597,000 deaths worldwide in 2023. About 95 percent of deaths occur in the WHO African Region, and children under five account for around three quarters of those deaths. Nigeria, the Democratic Republic of the Congo, Uganda, Ethiopia and Mozambique carry a large share of the burden. Travellers returning from malaria areas also develop malaria every year in Europe and North America.

How malaria spreads

• Bites from infected female Anopheles mosquitoes, mostly between dusk and dawn
• From mother to baby during pregnancy or birth (congenital malaria)
• Rarely, through blood transfusions, organ transplants or shared needles
• It does not spread through casual contact, coughing or sneezing

Who is most at risk?

• Children under five, who have not yet developed partial immunity
• Pregnant women, especially in a first pregnancy
• People living with HIV
• Travellers and migrants visiting family in malaria areas, who may have lost immunity
• People with sickle cell disease or without a working spleen
• Older adults and people with other serious illnesses

Symptoms of malaria

Symptoms usually start 7 to 30 days after an infected bite, but can appear months later, especially with P. vivax or P. ovale or if preventive tablets were taken. Early symptoms are often mild and easily mistaken for flu or another fever.,Common symptoms include fever, chills and shivering, sweating, headache, muscle aches, tiredness, nausea, vomiting, loss of appetite and diarrhoea. In children, fever, irritability, poor feeding, vomiting and drowsiness are common. The classic pattern of fever every 48 or 72 hours is often absent, especially early on.

Severe malaria: warning signs

• Confusion, extreme drowsiness, difficult to wake, or fits (seizures)
• Unable to sit, stand or feed
• Difficulty breathing or very fast breathing
• Repeated vomiting so medicines cannot be kept down
• Very pale palms or gums (severe anaemia)
• Yellow eyes or skin
• Dark or cola-coloured urine, or passing very little urine
• Unusual bleeding
• Cold hands and feet or collapse

Why severe malaria is an emergency

Severe malaria, usually caused by P. falciparum, can affect the brain (cerebral malaria), lungs, kidneys and blood. It can kill within 24 to 48 hours without treatment. Anyone with a warning sign needs to be taken to a hospital or health facility immediately. Intravenous or intramuscular artesunate is the recommended treatment, and in remote areas a single dose of rectal artesunate may be given to young children before transfer.

Always test before treating

Many people treat every fever as malaria, but WHO recommends that every suspected case is confirmed by a test before treatment. Fever has many causes, including typhoid, pneumonia, urinary infections, dengue and viral illnesses. Treating malaria that is not there wastes medicine, contributes to drug resistance, and can delay treatment of the real cause.,Testing is quick. Rapid diagnostic tests (RDTs) use a finger-prick of blood and give a result in about 15 to 20 minutes. Microscopy of a blood film remains the gold standard in many hospitals and can show the species and how many parasites are present. A negative test with ongoing fever should be repeated or other causes considered.

Treatment of uncomplicated malaria

For uncomplicated P. falciparum malaria, WHO recommends artemisinin-based combination therapy (ACT). Common options include artemether-lumefantrine, artesunate-amodiaquine, artesunate-mefloquine, dihydroartemisinin-piperaquine and artesunate-pyronaridine. Treatment usually lasts three days.,Take every dose, even if you feel better after the first day. Artemether-lumefantrine is best taken with fatty food or milk to improve absorption. If vomiting occurs within 30 minutes of a dose, the dose should usually be repeated. Return for review if the fever has not settled after three days or if symptoms get worse.

Treating P. vivax and P. ovale

These species can stay dormant in the liver and cause relapses. After treating the blood stage, a course of primaquine or a single dose of tafenoquine may be given to clear the liver stage. Both can cause dangerous breakdown of red blood cells in people with G6PD deficiency, so a G6PD test is recommended before treatment. Primaquine is not given in pregnancy or to very young infants.

Avoid fake and substandard medicines

Counterfeit and poor-quality antimalarials are a serious problem in some regions. Buy medicines from registered pharmacies or health facilities, check packaging and expiry dates, and be wary of very cheap products from street sellers. Monotherapy (artemisinin alone) should not be used, because it encourages resistance. Report suspected fake medicines to your national regulator.

Drug resistance

Partial resistance to artemisinin has emerged in South-East Asia and, more recently, in parts of East Africa, including Rwanda, Uganda, Eritrea and Ethiopia. Partner drug resistance also threatens ACTs. This is why testing before treatment, taking full courses, and using quality-assured medicines matter for everyone, not just the individual patient.

Malaria in children

Children under five are at the greatest risk of dying from malaria. Any fever in a child living in or returning from a malaria area should be tested promptly, ideally the same day. Do not wait to see if it settles, and do not rely on leftover medicines.,Dosing of antimalarials depends on weight, so a health worker should weigh the child. Give fluids, continue breastfeeding, and use paracetamol for fever as advised. Return immediately if the child becomes drowsy, has a fit, cannot drink, vomits everything, breathes fast or becomes very pale.

Malaria in pregnancy

Malaria in pregnancy increases the risk of severe anaemia, miscarriage, stillbirth, premature birth and low birth weight. Pregnant women in areas with high transmission in Africa are offered intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) at antenatal visits from the second trimester, at least three doses.,Sleeping under an insecticide-treated net every night is essential. ACTs, including artemether-lumefantrine, are now recommended by WHO for uncomplicated malaria in all trimesters. Pregnant women should avoid travelling to malaria areas if possible.

Insecticide-treated nets

Sleeping under a long-lasting insecticide-treated net (ITN) is one of the most effective ways to prevent malaria. Nets reduce child deaths and protect everyone sleeping under them. Newer dual-active-ingredient nets (such as those with chlorfenapyr) are more effective where mosquitoes have become resistant to older insecticides.,Use the net every night, all year, not only in the rainy season. Tuck the edges under the mattress, repair holes promptly, and hang it so it does not touch your skin. Wash it gently and dry it in the shade, and replace it about every three years or when badly damaged.

Indoor spraying and the home environment

• Indoor residual spraying with insecticide in many malaria programmes
• Screens on windows and doors, and closing them at dusk
• Clearing stagnant water from containers, tyres and blocked drains
• Covering water storage tanks
• Keeping grass short around the home
• Using fans or air-conditioning where available

Personal protection from bites

• Use an insect repellent containing DEET (20 to 50 percent), picaridin (icaridin), IR3535 or oil of lemon eucalyptus (PMD) on exposed skin
• Apply sunscreen first and repellent second
• Wear long sleeves and trousers from dusk
• Treat clothing with permethrin for extra protection
• Use mosquito coils or plug-in vaporisers indoors with care

Seasonal malaria chemoprevention

In parts of the Sahel and other areas where malaria peaks in the rainy season, children aged 3 to 59 months receive monthly sulfadoxine-pyrimethamine plus amodiaquine during the high-transmission months. This has been shown to prevent around three quarters of malaria cases in young children during the season. Perennial malaria chemoprevention for infants is also used in some countries.

Malaria vaccines

Two malaria vaccines are recommended by WHO for children living in areas with moderate to high transmission of P. falciparum: RTS,S/AS01 (Mosquirix), recommended in 2021, and R21/Matrix-M, recommended in 2023. They are given as a series of four doses from around five months of age.,By 2025, more than 20 African countries had introduced malaria vaccines into routine childhood immunisation, including Nigeria, Ghana, Kenya, Cameroon and Côte d’Ivoire. The vaccines reduce malaria cases and severe malaria significantly, especially when combined with nets and seasonal chemoprevention, but they do not give complete protection, so other measures remain essential. There is currently no licensed malaria vaccine for adult travellers.

Advice for travellers

If you live outside a malaria area, including if you grew up in one but now live abroad, you are at risk when you travel. Immunity fades quickly after leaving. People visiting friends and relatives are one of the groups most often diagnosed with malaria after travel.,Get advice from a travel clinic, nurse or pharmacist at least four to six weeks before you go. Preventive tablets depend on your destination and health and may include atovaquone-proguanil, doxycycline or mefloquine. Start them before travel as directed, take them regularly during the trip, and continue after you return for the recommended time, which can be one to four weeks.

Fever after travel

Any fever within a year of returning from a malaria area, especially in the first three months, should be treated as possible malaria until proven otherwise. Seek medical care the same day and tell the healthcare provider where you have travelled. Ask for a malaria test. Falciparum malaria in a non-immune person can become severe very quickly.

Common myths about malaria

• Myth: Every fever is malaria. Fact: Many fevers have other causes; always test
• Myth: You cannot get malaria if you grew up in Africa. Fact: Immunity is partial and fades after living elsewhere
• Myth: Malaria is spread by drinking dirty water or eating mangoes. Fact: It is spread by mosquito bites
• Myth: Stopping treatment once you feel better is fine. Fact: Incomplete treatment can lead to relapse and resistance
• Myth: Herbal teas can replace antimalarials. Fact: Only proven medicines cure malaria
• Myth: Nets are only needed in the rainy season. Fact: Transmission happens all year in many areas

Recovery after malaria

After successful treatment, tiredness and weakness can last for a week or two, and anaemia can take several weeks to recover. Eat a balanced diet with iron-rich foods, rest, and drink plenty of fluids. Children who have had severe malaria, especially cerebral malaria, should be followed up for problems with learning, behaviour or hearing.

Malaria and other conditions

People with sickle cell disease, HIV or without a spleen are at higher risk of severe malaria and need strict prevention. Some medicines interact with antimalarials, including certain HIV medicines, anti-epileptics and heart medicines, so tell the healthcare provider or pharmacist about everything you take.

The road to elimination

Many countries have eliminated malaria in recent decades. WHO has certified more than 40 countries and territories as malaria-free, including Cabo Verde and Egypt in 2024 and Georgia, Suriname and Timor-Leste in 2025. Progress depends on funding, strong health systems, new tools such as vaccines and better nets, and community action. Cuts in international health funding threaten these gains.

When to seek help: a quick summary

• Any fever in a malaria area: get tested the same day
• Fever in a child under five: do not wait, go now
• Fever after travel: tell the clinician where you have been
• Any warning sign of severe malaria: emergency care immediately
• Symptoms not improving after three days of treatment: return for review

The malaria life cycle in plain language

When an infected mosquito bites, it injects tiny parasites called sporozoites into the blood. Within an hour they reach the liver, where they multiply silently for one to two weeks, causing no symptoms. They then burst out into the bloodstream and invade red blood cells.

Inside red blood cells, the parasites multiply again and burst the cells, releasing more parasites that infect new cells. This repeated destruction causes fever, chills and anaemia. Some parasites develop into sexual forms that are picked up by the next mosquito to bite, continuing the cycle. Breaking the cycle at any point, by preventing bites, killing mosquitoes, or treating infected people quickly, reduces transmission.

What happens at the clinic

A nurse or other health worker will ask about your symptoms, travel and any medicines you have already taken, check your temperature, pulse, breathing and level of alertness, and look for warning signs such as pale palms, yellow eyes or difficulty breathing. A finger-prick test is done for malaria.

If the test is positive and there are no danger signs, you will usually be given a three-day ACT course to take at home, with clear instructions. If danger signs are present, treatment with injectable artesunate begins straight away and you will be admitted. If the test is negative, the health worker will look for other causes of fever.

Caring for someone with malaria at home

• Give every dose of the medicine at the right time, with food if advised
• Offer plenty of fluids and continue breastfeeding babies
• Use paracetamol to reduce fever and discomfort as directed
• Sponge with lukewarm (not cold) water if the fever is very high
• Let them rest, and keep them under a net so mosquitoes cannot spread the infection further
• Watch closely for warning signs and return immediately if any appear

Malaria and climate change

Rising temperatures, changing rainfall patterns and flooding can expand the areas and seasons where malaria mosquitoes thrive, including higher-altitude areas of East Africa that were once largely free of malaria. An invasive mosquito species, Anopheles stephensi, which breeds in urban water containers, has spread from Asia into the Horn of Africa and parts of West Africa, raising concern about urban malaria. Covering water stores and community clean-up campaigns help.

Malaria in the workplace

Malaria causes millions of lost working and school days every year. Employers in malaria areas can reduce sickness absence by providing nets, encouraging prompt testing, allowing time off for treatment, and supporting staff who travel. Healthcare workers should lead by example by using nets and testing before treating.

Diagnosing malaria in non-endemic countries

In countries where malaria is rare, it can be missed because healthcare providers may not think of it. Always say if you have travelled, even if it was months ago, and ask directly for a malaria test. Three negative blood films taken 12 to 24 hours apart are usually needed to rule malaria out. Severe falciparum malaria in travellers is treated in hospital, often with intravenous artesunate.

Community health workers

In many countries, trained community health workers test and treat malaria in villages far from clinics, using rapid tests and ACTs. They also refer children with danger signs and give rectal artesunate before transfer. This approach, called integrated community case management, has saved many lives by bringing care closer to home. Find out who your local community health worker is and how to reach them.

What governments and communities can do

• Fund free testing and treatment at the point of care
• Distribute nets through mass campaigns and antenatal clinics
• Roll out malaria vaccines alongside other childhood vaccines
• Track drug and insecticide resistance
• Strengthen supply chains so medicines never run out
• Involve communities in clean-up and education

Talking to children about malaria

Children can learn simple habits early: sleeping under the net every night, telling an adult when they feel hot or unwell, and helping to empty water containers around the home. Schools are powerful places to share these messages.

Frequently asked questions

How long does it take to recover from malaria?

Most people feel better within a few days of starting treatment, but tiredness can last a week or two. Severe malaria can take much longer.

Can you get malaria more than once?

Yes. Having malaria does not give lasting protection, and people in high-transmission areas can be infected many times.

Do I need to take malaria tablets if I am only visiting for a few days?

Usually yes, if your destination has a significant malaria risk. Even a short trip can result in infection.

Can malaria come back years later?

P. vivax and P. ovale can relapse months or occasionally years later from dormant liver stages unless treated with primaquine or tafenoquine.

Is malaria contagious between people?

No, apart from rare cases through blood, organ transplants or from mother to baby.

Can I donate blood after having malaria?

Rules vary by country, but most blood services ask people to wait a set period, often three years, after malaria or living in a malaria area before donating.

But I have had malaria many times. Why should I bother testing?

Because the fever you think is malaria might be something else that needs different treatment, and because repeated self-treatment with incomplete or poor-quality medicines fuels resistance. A test takes 20 minutes. For a child, it can be the difference between a simple illness and a hospital admission.

Related: Malaria nursing care · Severe malaria and artesunate · Malaria in pregnancy · Travel vaccines and malaria tablets

Sources: World Health Organization (World Malaria Report 2024, WHO Guidelines for Malaria), US Centers for Disease Control and Prevention, UK Health Security Agency, Medicines for Malaria Venture.