Roseola: a few days of high fever, then a rash

A few days of high fever in a toddler who still plays and eats, then a pink rash just as the temperature drops: that is the typical roseola story. The catch is that only the rash confirms it, so until it appears you treat your child like any other child with a fever.

Written by OUMM

Last updated: 9 October 2026

What roseola is

Roseola (roseola infantum, sometimes called sixth disease) is a common viral infection of young children, usually caused by human herpesvirus 6 (HHV-6), less often HHV-7. According to the American Academy of Pediatrics (AAP), almost all children get it in their first 2 years, most often between 6 months and 2 years. It is usually mild and goes away on its own.

How it goes: fever first, rash second

1. A sudden high temperature. The AAP gives 102-105 °F (38.9-40.6 °C) for 3-5 days; the NHS says the early symptoms last 3-7 days. Despite the fever, most children do not seem very sick and stay active and playful (AAP).
2. Sometimes cold-like symptoms: runny nose, cough, sore throat, loss of appetite, swollen glands or eyelids (NHS); some children are fussy, vomit or have diarrhoea (AAP).
3. A rash as the fever goes. Small pink-red spots and bumps, starting on the chest, tummy and back and spreading to the neck and arms. It is not usually itchy. On brown or black skin it may be harder to see. It fades on its own: within about 2 days (NHS) or 1-4 days (AAP), turns pale when pressed and leaves no marks (mp.pl).

Why it is diagnosed in hindsight

Doctors diagnose roseola from the story of the symptoms, the order in which they came and the rash once it has appeared (AAP), often together with basic blood tests (mp.pl). In the first days all you see is a high fever, which has many possible causes, some of which need treatment. So until the rash shows up, do not assume "it is just roseola": watch your child and follow the same rules as for any fever, set out in fever in children.

What you can do at home

• Fluids: often, in small amounts. Wet nappies (diapers) are a good sign.
• Rest and light clothing; do not bundle your child up (NHS).
• A fever medicine (paracetamol, called acetaminophen in the US, or ibuprofen) when your child is distressed, not to chase a number. There is no specific treatment and no antibiotic for roseola itself; the aim is comfort and fluids (AAP). Take the dose from your product's leaflet table: see the dose calculator, and paracetamol or ibuprofen for choosing between them.
• Write down the times of readings, doses and how much your child drinks. At the doctor's it shows at a glance how long the fever has lasted.

Febrile seizures

The high temperature of roseola can trigger a febrile seizure in some young children (NHS). The child goes stiff, twitches, shakes or jerks; it usually lasts 2-3 minutes (NHS). Lay your child on their side, put nothing in their mouth and time it. For a first seizure, or one lasting over 5 minutes, call 999 in the UK or 911 in the US. Fever medicines do not prevent seizures. More in the febrile seizures section of fever in children.

When to see a doctor

Roseola usually settles by itself, but these rules apply before you know that is what it is:

• Under 3 months with 38 °C (100.4 °F) or more: urgently, also at night.
• 3-6 months with 39 °C (102.2 °F) or more, and any child at 39 °C or more (a cautious rule of this site, not a guideline threshold): contact a doctor.
• Fever for more than 3 days: see a doctor. Roseola fever can last longer, but without the rash you cannot know it is roseola. The NHS advises an urgent GP appointment or 111 at the latest when a high temperature has lasted 5 days or longer.
• Refusing drinks or feeds, few wet nappies or other signs of dehydration (NHS, AAP).
• Very sleepy and hard to wake: get help right away (AAP).
• The rash turns into blisters or sores, or affects the lips and the inside of the mouth (AAP).
• A rash that does not fade when you press a glass against it: that is not roseola, call emergency services (NHS).

The full list of red flags by age is in when to see a doctor with a child's fever.

Is roseola contagious?

Yes. The virus spreads through coughing and sneezing (AAP), and children often catch it from people who have no symptoms themselves (mp.pl). The NHS says it is thought to be most contagious while the temperature is high, so keep your child at home then. Once the fever has passed and they feel well enough, they can go back to nursery without waiting for the rash to fade (NHS). The AAP is more cautious: back to daycare after 24 hours without a fever.

Common questions

Can roseola happen without a rash?

The rash is typical, but at home you cannot tell a fever without a rash apart from other infections. Until the rash appears, the usual fever rules apply.

Does the rash itch, and does it need a cream?

It is not usually itchy or uncomfortable and fades on its own within a few days (NHS, AAP).

Does my child need blood tests?

Often, yes. According to mp.pl, the diagnosis usually rests on the history, the order of symptoms and basic blood tests (blood count with smear, ESR, CRP), and tests done on the third day of fever tell the most. Whether and when to test is for the doctor to decide.

Can my child get roseola twice?

Having had it usually leaves lasting immunity, but because more than one virus can cause it, a second infection with another of them is possible (mp.pl). Each time, judge the fever by how your child is, not by the name of the illness.

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