Scarlet Fever in Babies

When to get help

See a GP if you think your baby has scarlet fever. Unlike most rashes on this site, this one needs a prescription. The NHS says a GP will prescribe antibiotics, which help recovery, reduce the chance of a serious illness such as pneumonia, and make it less likely the infection is passed on. Scarlet fever spreads very easily, so call the surgery before going in — they may suggest a phone consultation.

Also see a GP if your baby does not get better within a week of being seen, has scarlet fever and chickenpox at the same time, or becomes ill again weeks after recovering — the NHS notes this can be a sign of a complication such as rheumatic fever.

Ask for urgent advice — NHS 111 in the UK (call rather than use the website for a child under 5), GP out-of-hours in Ireland, your paediatrician in the US or Canada, healthdirect on 1800 022 222 in Australia, Healthline on 0800 611 116 in New Zealand — if your baby is under 3 months with a temperature of 38°C (100.4°F) or higher, is 3 to 6 months with 39°C (102.2°F) or higher, will not feed, or has fewer wet nappies than usual.

Call emergency services — 999, 112, 911, 000 or 111 by country — if your baby has a rash that does not fade under a pressed glass, difficulty breathing, blue, grey or mottled skin, a stiff neck, a first seizure, or cannot be roused. The scarlet fever rash blanches; a rash that does not is a different emergency.

What it looks and feels like

The first signs are flu-like: a high temperature, a sore throat, and swollen neck glands that feel like a large lump on the side of the neck. The NHS says a rash appears 12 to 48 hours later.

The rash is the distinctive part. It looks like small, raised bumps, starts on the chest and tummy and then spreads, and it makes the skin feel rough, like sandpaper. On white skin it looks pink or red. On brown and black skin a colour change may be harder to see, but you can still feel the rash and see the raised bumps. That is the key practical point: this is a rash you can diagnose with your fingertips when your eyes are not helping.

Two other features. A white coating appears on the tongue, then peels to leave the tongue red, swollen and covered in little bumps — the so-called strawberry tongue. And the rash does not appear on the face, though the cheeks can look red, which again may be harder to see on brown and black skin. As the rash fades, the skin sometimes peels like sunburn.

How common is it in babies?

Less common than you would think from the amount of coverage it gets. The CDC says scarlet fever is most common in children aged 5 through 15, and less common in children younger than 3. A baby with an unexplained fever and a rough rash still needs seeing, but this is not the top of the list for the under-ones.

The CDC also notes the incubation period: it usually takes two to five days after exposure for symptoms to begin, and that close contact with someone who has it is the commonest risk factor, with household spread being typical. Parents of school-age children are specifically named as being at increased risk, which matters if there is an older sibling at school.

Antibiotics, and the 24-hour rule

Scarlet fever is caused by group A Streptococcus, and it is one of the few common childhood rashes that is bacterial rather than viral. That is why the advice differs so sharply from chickenpox or roseola.

The NHS gives the contagious window plainly: you can spread scarlet fever until 24 hours after the first dose of antibiotics. Without antibiotics, you can spread the infection for two to three weeks after symptoms start. The exclusion rule follows directly: stay away from nursery, school or work for 24 hours after the first dose. UKHSA guidance for education and childcare settings uses the same threshold.

Finish the course even once your baby seems better. The NHS states this explicitly, and it is not a formality — the point of completing treatment is to reduce the risk of the later complications below.

What helps alongside the antibiotics

• Cool fluids. For a baby, normal feeds offered more often.
• Soft foods if your baby is on solids and has a sore throat.
• Paracetamol to bring down a high temperature, if your baby is distressed. Check the label for suitability at their age and weight, or ask a pharmacist.
• No aspirin for children under 16.
• Calamine lotion can ease itching. Ask a pharmacist which itch treatments suit a baby.

Scarlet fever lasts around a week.

Complications, and the one to watch for later

The NHS says complications are rare but can happen during or in the weeks after the infection, and lists ear infection, throat abscess, sinusitis, pneumonia, meningitis and rheumatic fever. The CDC makes the same point that complications after scarlet fever are not common but can occur.

The delayed ones are the reason for that unusual instruction to go back if your child becomes ill again weeks after recovering. Most people expect a follow-up window of days, not weeks. If a baby who had scarlet fever a month ago develops a fever, joint swelling or breathlessness, mention the scarlet fever when you call.

Chickenpox at the same time

The NHS singles this combination out as a reason to see a GP, and it is worth understanding why: chickenpox breaks the skin, and broken skin is a route for streptococcal infection to become invasive. If your baby has chickenpox and develops a high temperature that is climbing rather than settling, or areas of skin that become hot, red and swollen, that is a same-day call rather than a wait.

Pregnancy

The NHS states there is no evidence that getting scarlet fever during pregnancy will harm the baby, but that it can make you feel unwell, so it is best to avoid close contact with anyone who has it. Many of the antibiotics used are suitable in pregnancy. Contact a GP if you develop symptoms.