The most common malaria symptoms are fever, headache and chills, according to the WHO. If you live in or have been to a malaria area and develop a fever, get a malaria test the same day. If you have any severe sign, such as multiple convulsions or difficulty breathing, go for emergency care right away.
- Key takeaways
- Early malaria symptoms
- Same-day test or emergency care: a checklist
- Why you need a test before treatment
- Groups at higher risk of malaria
- How to prevent malaria
- Malaria vaccines for young children
- Malaria in East Africa
- Myths vs facts
- Common mistakes
- Frequently asked questions
- How soon after a mosquito bite do malaria symptoms start?
- Can malaria be fatal?
- What is the difference between an RDT and microscopy?
- Does malaria cause problems in pregnancy?
- Can I have malaria without a fever?
- Limits of this guide
- Sources
Key takeaways
- Early malaria looks like flu: fever, headache and chills.
- The WHO recommends that every suspected case is confirmed with a parasite-based test, either microscopy or a rapid diagnostic test (RDT).
- Severe signs need emergency care immediately, because untreated falciparum malaria can become severe and fatal within 24 hours.
- Children under 5, pregnant women and people with HIV/AIDS are at higher risk.
- Nets, indoor spraying, repellent and, for young children, vaccines all lower the risk.
Early malaria symptoms
The WHO lists fever, headache and chills as the most common early symptoms. They usually appear 10 to 15 days after the mosquito bite, according to the WHO. The NHS gives a range of 7 to 18 days and says symptoms occasionally appear months later.
The CDC adds muscle aches, tiredness, nausea, vomiting and diarrhoea. The NHS describes feeling hot, cold or shivery, plus sweating, and says malaria can be hard to spot. Because these signs match many other illnesses, the symptoms alone cannot tell you that you have malaria. A blood test can.
Same-day test or emergency care: a checklist
The checklist below is built from the WHO’s list of severe signs. It is a guide to urgency, not a diagnosis. Same-day testing is this guide’s practical reading of the WHO, CDC and NHS advice to confirm suspected cases quickly.
Get tested the same day
- Fever, or feeling hot and shivery.
- Headache with chills or sweating.
- Muscle aches and tiredness with a fever.
- Nausea, vomiting or diarrhoea together with a fever.
The WHO recommends that all suspected malaria cases are confirmed by testing. In an area with malaria, that means a fever is a reason to visit a clinic or health post and ask for a test, not to wait and see. The CDC also says people who have symptoms and have been in a malaria area within the last year should see a provider as soon as possible.
Emergency now
- Extreme fatigue.
- Impaired consciousness.
- Multiple convulsions.
- Difficulty breathing.
- Dark or bloody urine.
- Jaundice, a yellow colour of the skin or eyes.
- Abnormal bleeding.
The WHO says people with severe symptoms should get emergency care right away. The CDC lists kidney failure, seizures, confusion and coma among the severe complications. Do not wait for a routine appointment, and do not wait to see whether a fever settles.
Why you need a test before treatment
The WHO recommends confirming suspected malaria with parasite-based testing, using either microscopy or an RDT. The CDC says a healthcare provider diagnoses malaria with a blood test.
The test matters because the right medicine depends on the result. The WHO says malaria always needs medicine, and the choice depends on the parasite type, drug resistance, the patient’s age and weight, and pregnancy. Artemisinin-based combination therapies (ACTs) are the most effective treatment for Plasmodium falciparum, according to the WHO. Medicine should come from a health worker, who will choose the drug and the amount. The CDC says prescription drugs can treat and cure malaria.
Groups at higher risk of malaria
The WHO names several groups that are at higher risk. The table summarises them with the WHO’s own points.
| Group | What the WHO says |
|---|---|
| Infants and children under 5 | Higher risk; children under 5 account for about 75% of deaths in the WHO African Region, according to the WHO fact sheet. |
| Pregnant women | Higher risk; malaria in pregnancy can cause premature delivery or low birth weight. |
| People with HIV/AIDS | Higher risk of malaria. |
| Travellers | Higher risk of malaria. |
Source: WHO malaria fact sheet.
This guide’s advice: parents of young children and pregnant women should treat any fever as a reason to seek a test promptly.
How to prevent malaria
The WHO names insecticide-treated nets and indoor residual spraying (IRS) as the core ways to control the mosquitoes that carry malaria. The NHS adds insect repellent (it says to use one with 50% DEET), long sleeves and trousers in the evening, and nets.
The WHO also describes two medicine-based measures for set high-risk periods: seasonal malaria chemoprevention and intermittent preventive treatment in pregnancy. The NHS advises travellers to ask for medical advice 4 to 6 weeks before they travel.
Malaria vaccines for young children
The WHO recommends two vaccines, RTS,S/AS01 and R21/Matrix-M, for young children in areas of moderate to high transmission. For RTS,S, the WHO says the first dose is given from about 5 months of age, in a series of 4 doses. The WHO says malaria vaccines should be provided as part of a comprehensive malaria control strategy, alongside measures such as bed nets.
Malaria in East Africa
In 2024 there were about 282 million malaria cases and 610,000 deaths in 80 countries, according to the WHO. The WHO African Region carried 95% of the cases (265 million) and 95% of the deaths (579,000). The MedlinePlus health library notes that the deadliest form of the parasite is found in sub-Saharan Africa.
Kenya is one of 25 African countries offering a malaria vaccine, according to the WHO’s RTS,S Q&A.
Myths vs facts
- Myth: If the fever goes away, the malaria has gone. Fact: The WHO says malaria always needs medicine, and a fever that eases is not a test result.
- Myth: Any fever is malaria. Fact: The symptoms resemble other illnesses, which is why the WHO recommends confirming with a test.
- Myth: A vaccine means you can stop using a net. Fact: The WHO says vaccines work best alongside other measures such as bed nets.
- Myth: Malaria only affects travellers. Fact: The WHO counts 95% of cases in the African Region, where many people live with the risk every day.
Common mistakes
- Waiting at home when a child under 5 has a fever.
- Starting leftover medicine without a test or a health worker’s advice.
- Ignoring confusion, convulsions or dark urine because the person “only has a fever”.
Frequently asked questions
How soon after a mosquito bite do malaria symptoms start?
The WHO says usually within 10 to 15 days. The NHS says 7 to 18 days, and occasionally months.
Can malaria be fatal?
Yes. The WHO says untreated P. falciparum malaria can become severe and fatal within 24 hours, and MedlinePlus says malaria can be life-threatening. Early testing and treatment lower that risk.
What is the difference between an RDT and microscopy?
Both are parasite-based blood tests that the WHO accepts for confirming malaria.
Does malaria cause problems in pregnancy?
The WHO says malaria in pregnancy can cause premature delivery or low birth weight.
Can I have malaria without a fever?
None of the sources used here says whether malaria can occur without a fever. The WHO says symptoms can be mild, especially in people who have had malaria before. If you feel unwell in a malaria area, ask a health worker whether to be tested.
Limits of this guide
This guide covers warning signs and testing in general terms. It does not give medicine amounts, and it cannot say whether you or your child has malaria.
This article is general information and is not medical advice. Talk to a doctor or qualified health professional before you change your treatment.
Last reviewed: October 2026
