Rash with Fever in a Child Algorithm

Safety

Red Flags — Meningococcal Disease, Sepsis & the Seriously Ill Child

Done

Fever with a rash is usually viral, but meningococcal disease can kill within hours. Look at the whole child first, then the rash. For the full feverish-child pathway see the Fever in children algorithm.

Non-blanching (petechial or purpuric) rash with fever Or any child who looks ill with a rash → 999 immediate transfer. If meningococcal disease is strongly suspected, give IM/IV benzylpenicillin or ceftriaxone before transfer unless this would delay it (NICE NG240) — dose by age per BNFC

Signs of shock or sepsis Mottled, pale or blue skin, cold hands and feet, weak pulse, raised RR, drowsy or floppy, reduced urine output → 999

Suspected meningitis Neck stiffness, bulging fontanelle, photophobia, altered consciousness, seizure, irritability when handled → 999. Classic signs are often absent in infants

Infant under 3 months with temperature 38°C or more → Urgent paediatric assessment (generally ≤2 h); 999 if shocked, poor breathing, reduced consciousness or seizure (NICE NG143)

Fever for 5 days or more with red eyes, red lips or tongue, rash, swollen hands or feet, neck node Kawasaki disease (incomplete forms common in infants) → Same-day paediatric assessment

Invasive group A strep (iGAS) features Scarlet fever or chickenpox with severe pain out of proportion, rapidly spreading redness or swelling, persistent high fever, toxic appearance → 999

Blisters, skin pain or mucosal involvement Eczema herpeticum (punched-out erosions on eczema), SJS/TEN, staphylococcal scalded skin → Same-day paediatric / dermatology assessment

Vulnerable child with chickenpox or measles Neonate, immunosuppressed (chemotherapy, high-dose steroids, biologics) or exposed while vulnerable → Same-day specialist advice (antivirals, immunoglobulin)

Early meningococcal disease may show a blanching maculopapular rash, or no rash at all; leg pain, cold extremities and abnormal skin colour can come before the classic signs. A glass test is not sufficiently reliable to exclude meningococcal disease. NICE NG240 (2024) advises IV or IM ceftriaxone or benzylpenicillin outside hospital for strongly suspected meningococcal disease unless it would delay transfer; benzylpenicillin is more often carried in GP bags. Do not give it if the child has had a severe allergic reaction to either antibiotic.

iGAS can complicate scarlet fever and chickenpox; it is uncommon but has a high mortality and progresses quickly.

Diagnose

Assess the Child — NICE NG143 Traffic Light & History

Done

Traffic light (under 5s)

Green: normal colour, responds normally, content or smiles, normal cry, moist mucous membranes. Amber: pallor reported by parent, not responding normally, reduced activity, nasal flaring, SpO₂ ≤95% in air, capillary refill ≥3 s, dry mucous membranes, poor feeding, age 3–6 months with temperature ≥39°C, fever for 5 days or more, rigors, limb or joint swelling. Red: pale, mottled, ashen or blue, no response to social cues, appears ill, weak, high-pitched or continuous cry, grunting, RR >60, moderate or severe chest indrawing, reduced skin turgor, bulging fontanelle, neck stiffness, focal signs, non-blanching rash (NICE NG143)

Age 5 and over

NG143 is not validated: use the same principles — appearance, circulation, breathing, hydration, conscious level and parental concern

Rash history

Where it started, how it spread, itch, blisters, timing relative to the fever (rash as fever falls → roseola)

Associated features

Sore throat, cough, coryza, conjunctivitis, mouth ulcers, joint pain, abdominal pain, limb pain, vomiting, poor feeding, urine output

Contacts and outbreaks

Nursery or school cases (chickenpox, scarlet fever, measles), household contacts, travel abroad

Vaccination

MMR or MMRV doses (measles, chickenpox), MenB, MenACWY, Hib/MenC — an unvaccinated child with fever, cough, conjunctivitis and rash has measles until proven otherwise

Medicines and risk

Recent antibiotics (amoxicillin rash with EBV), new drugs; eczema, immunosuppression, sickle cell disease, asplenia; pregnant household members

Parental concern

Take it seriously — "this is different" is an important amber flag

The traffic light system supports, but does not replace, clinical judgement. Height of fever alone does not reliably identify serious illness. Asking about pregnant contacts matters for chickenpox, measles, rubella and parvovirus B19.

Diagnose

Examine the Whole Child and the Whole Skin

Done

Observations

Temperature (axillary electronic under 4 weeks; axillary or tympanic from 4 weeks to 5 years), HR, RR, SpO₂, capillary refill, hydration, conscious level; BP if available

Undress fully

Including the nappy area. Check conjunctivae, palms, soles and the mouth — petechiae and colour change are harder to see on brown and black skin

Blanching

Blanching (viral, scarlet fever, drug, urticaria) versus non-blanching (petechiae, purpura). The glass test helps describe a rash but cannot exclude meningococcal disease

Morphology

Maculopapular, sandpaper-like (scarlet fever), vesicles in crops (chickenpox), vesicles on hands, feet and mouth (HFMD), red cheeks then lacy limbs (slapped cheek), wheals (urticaria), target lesions (erythema multiforme)

Mouth and eyes

Koplik spots (measles), strawberry tongue (scarlet fever, Kawasaki), cracked red lips, exudative tonsillitis, mouth ulcers; non-purulent conjunctivitis (Kawasaki, measles)

Other

Neck stiffness, fontanelle, lymph nodes, liver and spleen, joints, chest, ears and throat for a source; peeling hands and feet (late scarlet fever or Kawasaki)

Petechiae only above the nipple line after forceful coughing or vomiting can be benign in a well child, but only after full assessment and a period of observation; if in doubt, treat as meningococcal disease. Unexplained petechiae, especially with pallor, bruising or hepatosplenomegaly, need immediate paediatric assessment (leukaemia — NICE NG12). See the Purpura and petechiae algorithm.

Diagnose

Pattern Recognition — Common Fever-and-Rash Illnesses

Done

Meningococcal disease

Rapidly evolving petechiae or purpura, ill child; may start blanching. Notifiable

Measles

2–4 days of fever, cough, coryza and conjunctivitis; Koplik spots; maculopapular rash from behind the ears and face spreading down by day 3–4; miserable child; often unvaccinated. Notifiable

Scarlet fever

Typically 2–8 years: sore throat, fever, headache; fine sandpaper rash on the trunk 12–48 hours later, flushed cheeks with pale around the mouth, strawberry tongue; later peeling. Notifiable

Kawasaki disease

Fever for 5 days or more plus 4 of: bilateral non-purulent conjunctivitis; red cracked lips or strawberry tongue; red or swollen hands and feet (later peeling); polymorphous rash; cervical node over 1.5 cm. Infants may have incomplete features

Chickenpox

Itchy crops of papules → vesicles → crusts, mostly trunk and face, mild fever. Complications: bacterial skin infection, pneumonia, cerebellar ataxia, encephalitis, iGAS

Hand, foot and mouth disease

Under 10s: mild fever, painful mouth ulcers, oval grey vesicles on hands, feet and buttocks; usually mild

Slapped cheek (parvovirus B19)

Mild illness, then bright red cheeks, followed by a lacy rash on limbs; child well and no longer infectious once the rash appears. Risk to pregnant contacts and children with haemolytic anaemia

Roseola (HHV-6)

6 months to 2 years: 3–5 days of high fever in a well child, then a pink macular rash as the fever settles; febrile seizures possible

Others

Non-specific viral exanthem (commonest), rubella (notifiable), urticaria, EBV with amoxicillin rash, eczema herpeticum, impetigo, IgA vasculitis (palpable purpura on legs and buttocks), drug reaction, Lyme disease (erythema migrans) — see the Maculopapular rash algorithm

Untreated Kawasaki disease causes coronary artery aneurysms in about a quarter of children; treatment within 10 days of fever onset greatly reduces this. Measles is resurgent in England with falling MMR uptake, and it can cause pneumonia, encephalitis and, years later, SSPE.

Diagnose

Tests & Notification — Mostly a Clinical Diagnosis

Done

Notify on clinical suspicion

Measles, rubella, scarlet fever, invasive group A strep and meningococcal disease are notifiable: the registered medical practitioner informs the local UKHSA Health Protection Team — do not wait for confirmation (Health Protection (Notification) Regulations 2010). Phone the HPT the same day for measles

Measles

The HPT arranges confirmation (oral fluid test kit or PCR swab) and contact assessment

Scarlet fever

Diagnose clinically; a throat swab is not needed before treatment but helps when the diagnosis is uncertain or in outbreaks

No obvious source

Urine sample in a febrile child under 5 without a clear source (NICE NG143)

Not in primary care

Do not delay transfer for blood tests in an ill child; Kawasaki and meningococcal investigations are done in hospital

Prompt notification lets the Health Protection Team protect vulnerable contacts — post-exposure MMR within 72 hours or immunoglobulin within 6 days of measles exposure for those who need it — and manage outbreaks in nurseries and schools.

Refer

Where Does This Child Go?

Done

999

Non-blanching rash with fever or an ill child; shock; suspected meningitis; seizure lasting 5 minutes or more; respiratory compromise; suspected iGAS or toxic shock

Urgent ≤2 h

Any other NG143 red feature; infant under 3 months with temperature 38°C or more — urgent paediatric assessment

Same-day

Suspected Kawasaki disease; eczema herpeticum; blistering or mucosal rash; complicated chickenpox (pneumonia, ataxia, drowsiness, dehydration, spreading skin infection); measles with complications or in an infant or immunosuppressed child; vulnerable contacts needing post-exposure treatment (specialist or HPT advice)

Amber features

Face-to-face assessment; paediatric assessment the same day if the clinical picture is concerning, otherwise a clear safety-net and planned review (NICE NG143)

Primary care manage

Green features with a recognisable self-limiting illness or scarlet fever — treat, notify where needed, give exclusion and safety-net advice

NICE NG143 asks for face-to-face assessment of children with amber features and a written safety-net or planned follow-up if they are sent home. Children with red features who are not immediately life-threatened still need urgent face-to-face paediatric assessment, generally within 2 hours.

Treat

Management at This Consultation

Done

Strongly suspected meningococcal disease

Benzylpenicillin or ceftriaxone + 999

IM or IV, as soon as possible, unless it would delay transfer or there is a severe allergy to the antibiotic (NICE NG240). Dose by age per BNFC. Oxygen if shocked or SpO₂ <92%. Pre-alert the hospital

Scarlet fever

Phenoxymethylpenicillin 10 days

First line for 10 days (UKHSA, NICE CKS); dose by age per BNFC. Penicillin allergy: a macrolide per UKHSA and local guidance (clarithromycin or azithromycin, BNFC). Notify the HPT. Off nursery or school until 24 hours after starting the antibiotic

Measles

Supportive · notify · isolate

Phone the HPT; keep the child out of the waiting room. Fluids, paracetamol or ibuprofen for distress. Off nursery or school for 4 days from the onset of the rash. Identify vulnerable contacts (pregnant, immunosuppressed, infants) for HPT advice. Check the family's MMR or MMRV status

Chickenpox

Paracetamol, fluids, itch relief

Avoid NSAIDs such as ibuprofen (risk of severe skin and soft tissue infection — NICE CKS). Emollient or calamine; a sedating antihistamine (e.g. chlorphenamine, from 1 year — BNFC) for itch disturbing sleep. Aciclovir is not routine in healthy children; consider it for those aged 14 and over seen within 24 hours of rash onset, and seek urgent advice for neonates, the immunosuppressed and pregnancy. Off nursery or school for at least 5 days from rash onset and until all spots have crusted over

HFMD · slapped cheek · roseola · viral exanthem

Supportive care

Fluids, paracetamol or ibuprofen if distressed. No exclusion needed while the child is well enough. Slapped cheek: advise pregnant contacts to contact their midwife or GP; same-day FBC and advice if the child has sickle cell disease or another haemolytic anaemia

Antipyretics (all)

For distress, not the number

Paracetamol or ibuprofen if the child is distressed; do not give both at the same time, consider alternating only if distress persists; no tepid sponging; antipyretics do not prevent febrile seizures (NICE NG143)

Next steps: see Impetigo · Eczema · Urticaria · Glandular fever

A 10-day course of phenoxymethylpenicillin is advised for scarlet fever to eradicate group A strep and reduce complications. NSAIDs in chickenpox have been associated with severe skin and soft tissue infections, including necrotising fasciitis. Kawasaki disease is treated in hospital with IVIG and aspirin — do not start aspirin in primary care.

Lifestyle

Home Care, Exclusion & Vaccination

Done

Exclusion (UKHSA)

Chickenpox: at least 5 days from rash onset and until all vesicles have crusted over. Measles: 4 days from rash onset. Scarlet fever: 24 hours after starting antibiotics. Rubella: 5 days from rash onset. Impetigo: until lesions crust or 48 hours after starting antibiotics. Hand, foot and mouth, slapped cheek, roseola: none if well

Vaccination

From 1 January 2026 MMRV (measles, mumps, rubella and varicella) replaced MMR in the routine UK schedule: children born on or after 1 January 2025 are offered doses at 12 and 18 months; older cohorts follow transitional schedules and a catch-up programme. Check status and offer any missed doses once well

Fluids Offer regular drinks (breastfeeding as usual); watch for fewer wet nappies, dry mouth, no tears.

Comfort Light clothing, normal room temperature; do not over- or under-dress.

Check the skin Look at the child and the rash regularly, including during the night.

Hygiene Handwashing, tissues, separate towels; keep nails short in chickenpox.

Pregnant contacts Pregnant women exposed to chickenpox, measles, rubella or slapped cheek should contact their midwife or GP promptly.

Childcare Keep at home while unwell, even when no formal exclusion applies.

Exclusion periods follow the UKHSA guidance for children and young people settings. Slapped cheek is infectious before the rash appears, so excluding a child with the rash has no public health benefit.

Safety

Follow-Up & Safety-Netting

Done

Amber features sent home

Written safety-net and a planned review (often within 24 hours) or direct access back (NICE NG143)

Scarlet fever

Complications are uncommon: return with ear pain, neck swelling, joint pain, dark urine or swelling, or a child getting worse after 48 hours of antibiotics

Fever for 5 days or more

Reassess face to face for Kawasaki disease and other serious causes

Safety-net 999

A rash that does not fade when a glass is pressed on it, the child is floppy, drowsy or hard to wake, has a fit, struggles to breathe, has blue lips, or has cold hands and feet with pale or mottled skin

Safety-net same-day

Fever for 5 days or more; not drinking or very few wet nappies; red eyes and lips with swollen hands or feet; chickenpox spots becoming red, hot, swollen or very painful, or fever coming back after a few days; the parent is more worried than before

Serious illness can evolve after the consultation. Clear, specific safety-net advice (verbal and written) and documentation are central to NICE NG143. In a remote consultation, any non-blanching rash or red feature converts to immediate face-to-face or emergency care.

🌡️ Rash with Fever in a Child

Red Flags — Meningococcal Disease, Sepsis & the Seriously Ill Child

Assess the Child — NICE NG143 Traffic Light & History

Examine the Whole Child and the Whole Skin

Pattern Recognition — Common Fever-and-Rash Illnesses

Tests & Notification — Mostly a Clinical Diagnosis

Where Does This Child Go?

Management at This Consultation

Home Care, Exclusion & Vaccination

Follow-Up & Safety-Netting