Fever in a child under 5 (IMCI)

WHO IMCI · reviewed October 2026 · gpreasoning.uk/global

Reasoning GP
Global Primary Care

Who / when

Children aged 2 months up to 5 years with a history of fever, who feel hot, or with an axillary temperature of 37.5 °C or above.
Young infants under 2 months with fever: use the sick young infant protocol (fever is a sign of possible serious infection).
Assess cough, diarrhoea, ear problems, nutrition and anaemia in the same visit.

Red flags: refer now

Not able to drink or breastfeed.
Vomits everything.
Has had convulsions, or is convulsing now.
Lethargic or unconscious.
Stiff neck.

Any one of theseVery severe febrile disease. Give the first dose of an antibiotic; in a malaria area also give pre-referral artesunate (or quinine); prevent low blood sugar; paracetamol for high fever; refer urgently.

Assess

Decide the malaria risk: high, low, or none (and any travel to a malaria area).
Ask: for how long? If more than 7 days, has it been present every day? Measles in the last 3 months?
Look and feel for stiff neck, runny nose, and any bacterial cause: local tenderness, mouth sores, refusing to use a limb, hot tender swelling, red tender skin or boils, pain passing urine in older children.
Look for measles: generalised rash with cough, runny nose or red eyes. Then look for mouth ulcers, pus from the eye and clouding of the cornea.
Malaria test (if no severe classification): in all fever cases where risk is high; where risk is low, if there is no obvious other cause.

Classify

No malaria test available: in high-risk areas, or in low-risk areas with no obvious other cause, classify as malaria.
Signs	Classify as	Action
Any general danger sign or stiff neck	Very severe febrile disease	Pre-referral treatment; refer urgently
Malaria risk and test positive	Malaria	First-line oral ACT; treat other causes; review in 3 days if fever persists
Test negative, or no malaria risk, no danger sign	Fever: no malaria	Treat the cause found (no antibiotic without a reason); review in 3 days (2 days if no malaria risk) if fever persists
Measles with clouding of cornea, deep or extensive mouth ulcers, or a danger sign	Severe complicated measles	Vitamin A, first dose of antibiotic, tetracycline eye ointment if eye signs; refer urgently
Measles with pus from the eye or mouth ulcers	Measles with eye or mouth complications	Vitamin A; treat eye and mouth; review in 3 days

Treat

Malaria: artemether-lumefantrine (20 mg/120 mg)

5 to under 15 kg: 1 tablet; 15 to under 25 kg: 2 tablets. Twice daily for 3 days (six doses), first two doses about 8 hours apart, with food.
Give the first dose in the clinic and watch for an hour; if vomited, repeat the dose. Or use your national first-line ACT.

High fever (38.5 °C or above): paracetamol every 6 hours

Age (weight)	100 mg tablet	500 mg tablet
2 months to 3 years (4 to under 14 kg)	1	1/4
3 to 5 years (14 to 19 kg)	1 1/2	1/2

Vitamin A for measles

6 to 12 months: 100 000 IU; 1 year and over: 200 000 IU. Not if a dose was given in the last month, or if the child is on RUTF.

Follow-up

Malaria, fever after 3 days: full reassessment. Do not repeat a positive RDT. Danger sign or stiff neck: treat as very severe febrile disease. Other cause: treat it. No other cause: microscopy if available; parasites after a full course: second-line antimalarial or refer.
Fever: no malaria, fever after 3 days: full reassessment and repeat the malaria test.
Fever every day for 7 days or more: refer for assessment.

Counsel

Give every dose of the medicine; finish the course.
Keep breastfeeding and give more fluids and food during the illness.
Sleep under an insecticide-treated net.
Return at once if the child cannot drink or breastfeed, becomes sicker, has a fit, or breathes fast or with difficulty.

The test shows malaria. Give these tablets twice a day for three days with food. Come back in three days if the fever is still there, or straight away if he cannot drink, has a fit or gets sicker.

When to refer

Urgently: any general danger sign, stiff neck, or severe complicated measles.
Fever present every day for more than 7 days.
Malaria with fever persisting after a full course and no microscopy or second-line treatment.
Measles eye infection that is not better after correct treatment; mouth ulcers that are worse or smell very foul.

Sources

World Health Organization. Integrated Management of Childhood Illness (IMCI) chart booklet. 2014. World Health Organization. WHO guidelines for malaria (10 September 2026 version). 2026.

Adapted from WHO guidance; not endorsed by WHO. This page paraphrases and adapts the WHO publications listed under Sources, which are licensed CC BY-NC-SA 3.0 IGO; the adapted text is shared under the same licence for non-commercial education. Reasoning GP is not affiliated with WHO or any other organisation named here. Use it alongside your national guidelines, essential medicines list and formulary, and your clinical judgement. Doses are given only where they come from a WHO source; otherwise follow your national guideline or formulary.