Fever Symptoms in Children: What Parents Should Know

Fever is one of the most common reasons parents bring their children to see a doctor. It often signals that the body is responding to an infection or inflammation, but it can still be worrying when a child feels hot, looks unwell or behaves differently. Understanding what causes a fever, recognising its symptoms, observing its progression, and knowing when to seek medical help can help you support your child confidently.

What Is a Fever?

A fever occurs when a child’s body temperature rises above the normal range, usually in response to infection or inflammation. For most children, a normal body temperature lies between about 36.5 °C and 37.5 °C. A reading of 38 °C or above is typically considered a fever. Fever itself is not a disease, it is a symptom that the immune system is active and working to fight off viruses, bacteria or other triggers.

How High Is “Too High,” and Does the Exact Temperature Always Matter?

Many parents focus on the number shown on the thermometer. While temperature can provide useful information, clinical guidance emphasises that how the child looks and behaves is often more important than the exact figure.

A temperature of 38 °C to 39 °C is common and often manageable at home if the child is drinking fluids, alert and relatively comfortable. Readings of 39.5 °C or higher, especially if sustained, may warrant closer monitoring and possibly a medical review. 

Extremely high temperatures (for example over 40 °C) may increase the risk of complications such as febrile seizures, but the presence of serious symptoms such as difficulty breathing, persistent vomiting, rash, or altered consciousness is more concerning than the number itself. Focus less on the thermometer reading alone and more on how the child is coping.

Can Teething Cause a Meaningful Fever in Babies or Is It Always Another Cause?

Teething is often cited as the cause of many symptoms in babies including irritability, drooling or mild temperature rise. However, authoritative clinical sources clarify that teething alone rarely causes a true fever of 38 °C or more.

If a baby has a genuine fever, you should consider other causes such as viral illness, ear infection or urinary tract infection. If teething appears the plausible trigger and the baby is otherwise feeding normally, active and drinking well, monitoring at home may be reasonable. 

However if additional symptoms appear such as rash, ear-tugging, refusal to feed, persistent fever or dehydration, you should contact your GP. Since teething and serious illness can overlap in presentation, when a baby is under three months old or has significant symptoms you should not assume teething is the cause without professional advice.

Can a Child’s Fever Stay Low-Grade for Days and Still Be Serious?

Yes. A low-grade fever (for example around 37.8 °C to 38 °C) that persists for several days may still signal an underlying issue even though it seems mild. Some infections or conditions may raise the child’s temperature only slightly but still cause other symptoms such as fatigue, poor appetite, persistent cough, ear pain or general unwell-being. If a low-grade fever persists beyond 48-72 hours, especially if the child remains unwell, not drinking properly or shows other symptoms, then a medical review is sensible. 

Recurrent low-grade fevers may also point to immune or inflammatory conditions which require investigation. In short, do not dismiss a mild fever simply because it is not high; the trend and associated symptoms matter.

Common Causes of Fever in Children

Fever can arise from various triggers. The most frequent causes are:

• Viral infections including common colds, influenza, ear infections, throat infections, gastroenteritis or other childhood viruses. These account for the majority of fevers in children.

• Bacterial infections such as pneumonia, urinary tract infections or tonsillitis may require antibiotics and warrant closer medical attention.

• Immunisations may produce mild fever within 24-48 hours of the vaccine, but this is usually benign and short-lived.

• Other causes include inflammatory disorders, drug reactions or overheating. The key is to monitor how the child behaves and whether additional symptoms are present.

Signs and Symptoms of Fever

When a child has a fever, you may notice:

• They feel hot to touch on the forehead, back or chest.

• Their skin appears flushed or warmer than usual; they may sweat or shiver.

• They appear more tired, irritable or clingy than usual.

• They have a reduced appetite, drink less and have less energy.

• Their breathing or heartbeat may be slightly faster than normal for age.

• They may cry more or seem unsettled without another clear cause.

Using a digital thermometer and following the instructions is helpful for tracking.

The Five Stages of Fever

Understanding how a fever typically progresses can help parents know what to expect:

1. Onset – Child feels cold or shivers as temperature starts to climb.

2. Temperature Rise – Fever develops and the child may become flushed or feel hot.

3. Peak Stage – The temperature is at its highest point. The child may be more uncomfortable, tired and less playful.

4. Plateau – The body maintains an elevated temperature while the immune system fights infection.

5. Cooling Down (Defervescence) – The fever begins to fall, the child may sweat, their skin may feel warm and they gradually recover.

While not every fever follows this exact pattern, the sequence provides a useful framework to anticipate changes.

When to Seek Medical Help For Children’s Fever

Although most fevers are mild and safe to manage at home, urgent medical advice is required if your child:

• Is under 3 months old and has a temperature of 38 °C or higher.

• Has a fever that lasts more than 3 days without improvement.

• Appears very unwell, is difficult to wake or has a change in responsiveness.

• Develops difficulty breathing, fast or shallow breathing, persistent cough or grunting.

• Refuses fluids, vomits repeatedly or shows signs of dehydration (dry mouth, very few wet nappies or no tears when crying).

• Develops a stiff neck, sensitivity to light or unusual rash especially one that does not fade when pressed (non-blanching rash).

• Experiences a seizure, especially their first one, or a seizure lasting more than five minutes.

If you are uncertain at any time, contact your GP or attend your nearest emergency department.

How to Care for a Child With Fever at Home

For many children with fever, home care is sufficient if they are comfortable and drinking fluids. Consider the following:

• Encourage fluids such as water, breast milk, formula or age-appropriate fluids to prevent dehydration.

• Dress them in light clothing to avoid overheating; keep the room at a comfortable temperature.

• Allow rest; children do not need to be forced to sleep, but provide a calm environment.

• Avoid cold baths or sponging as these can cause shivering and additional discomfort.

• Use paracetamol (correct formulation and dose for age/weight) if the child is uncomfortable or in pain. Ibuprofen may be used for children older than 3 months under the correct instructions. Do not give aspirin unless directed by a doctor.

• Monitor the child’s behaviour, drinking and temperature. If there is no improvement in 24-48 hours or the child’s condition worsens, see your GP.

Febrile Seizures

In some children (usually aged 6 months to 6 years) fever can trigger a febrile seizure. These are fits caused by a sudden rise in body temperature. Although frightening to watch, they are usually brief and do not cause long-term harm. When one occurs: turn the child onto their side, ensure their airway is clear, do not put anything in their mouth and seek urgent medical attention if the seizure lasts more than five minutes or it is the child’s first seizure.

When to See Your GP for Ongoing Concerns

Contact your GP if:

• Your child’s fever keeps recurring or you are concerned about an underlying cause.

• Your child is not improving despite home care and appears unwell.

• You would like investigation for frequent fevers, possible immune issues or repeated infections.

Your GP may recommend tests such as urine analysis, blood tests or throat/nose swabs to identify infection and guide treatment.

Supporting Your Child’s Health

Fever in children is often a normal part of growing up and fighting infections. In most cases the child will improve without complication. The main focus should be on how the child is coping, their fluid intake, responsiveness and any additional symptoms. Keep them comfortable, monitor closely and when in doubt, seek medical advice.

Disclaimer: This information is for general guidance only and not a substitute for professional medical advice. Always consult your GP or a qualified healthcare professional. For emergencies, dial 000.