Few symptoms cause parents as much anxiety as fever. Yet fever is not an illness: it is a normal response to infection, most often viral and self-limiting. The real question is therefore not "how high?" but "how is my child doing?".

At what point is it a fever?

Fever begins above 38 °C, measured rectally in infants — the most reliable method — or via the ear or forehead in older children. A temperature between 37.5 and 38 °C is not a fever: it may simply reflect physical activity, over-wrapping, or the end of the day.

Behaviour matters more than the number

A child at 39.5 °C who plays, drinks and smiles between naps is generally less concerning than a child at 38.3 °C who lies listless, refuses to drink and does not respond to those around them. Observe:

  • Is she drinking normally? Are her nappies as wet as usual?
  • Can he be comforted when you pick him up?
  • Does she return to activity between fever peaks?
  • Is his breathing calm and regular?

Signs that require immediate care

Go to the emergency department or call a doctor without delay if:

  • The child is under 3 months and has any fever at all. This is the most important rule — at this age an infection can progress very quickly.
  • There are red or purple spots that do not fade when pressed with a clear glass.
  • The child is abnormally drowsy, hard to rouse, or conversely inconsolable.
  • There is difficulty breathing: rapid breathing, drawing in between the ribs, flaring nostrils, bluish lips.
  • The neck is stiff or the child refuses to bend it.
  • The child refuses to drink for several hours, or vomits everything.
  • The child has had a seizure.
  • The fever lasts more than 3 days or returns after 24 hours without fever.

What helps at home

  • Offer drinks often, in small amounts. This is the single most important measure — fever causes dehydration.
  • Remove excess clothing without letting the child shiver, and keep the room around 19–20 °C.
  • Paracetamol at a weight-appropriate dose if the child is uncomfortable. The aim is comfort, not bringing the thermometer back to 37 °C.

Avoid cold baths and alcohol rubs, which cause significant discomfort and risk shivering. Ibuprofen should not be given during chickenpox or dehydration, and never without medical advice in infants. Aspirin is contraindicated in children.

What about febrile seizures?

They affect about 3 % of children between 6 months and 5 years. The episode is frightening to witness but is usually brief and leaves no lasting effects. Lay the child on their side, move anything that could injure them, put nothing in their mouth, and note the duration. A first seizure should always be medically assessed.

When teleconsultation is enough

For a child over 3 months, in good general condition, with an isolated fever for less than 48 hours, a remote opinion is often enough to decide: the doctor observes the child on screen, assesses breathing and behaviour, and tells you whether you need to travel. You can see a paediatrician by video quickly, including evenings and weekends.