Your child has suddenly developed a high fever, body aches, and no energy at all. Is it just a cold, or could it be the flu?
Influenza is a common viral illness that hits children hard — especially the youngest. Children under 5 are among those most at risk of complications. Fortunately, you can do a great deal at home to help your child feel as comfortable as possible, and it is important to know when to see a doctor.
What is the flu?
The flu is caused by influenza viruses (type A or B) and is an acute respiratory infection. The virus spreads through droplets (coughing, sneezing) and through contact with contaminated surfaces. Flu is highly contagious and spreads quickly in daycare centers and schools.
Flu season typically runs from November to April, peaking in January–February. Children are important spreaders because they shed the virus longer than adults — up to 7–10 days.
Symptoms of flu in children
The flu typically starts suddenly and forcefully, unlike a cold which builds gradually:
- High fever — often 102–104°F (39–40°C), can appear suddenly
- Chills and sweating — the child alternates between feeling cold and sweating
- Muscle aches and body pain — the child is clearly sore
- Headache — especially in older children
- Pronounced fatigue — the child is very listless and has little energy
- Dry cough — an irritating cough that can last for weeks after other symptoms have gone
- Sore throat — painful to swallow
- Loss of appetite — the child often does not want to eat
Flu in babies and infants
In babies under 1 year, symptoms can be harder to interpret:
- High fever without other obvious respiratory symptoms
- Irritability and restlessness — the baby cries more than usual and is hard to soothe
- Feeding refusal — does not want to breastfeed or drink
- Reduced activity — less movement and interest in surroundings
- Fast breathing or labored breathing
Babies under 3 months with a fever above 100.4°F (38°C) should always be evaluated by a doctor, regardless of cause. Call your pediatrician or an after-hours nurse line immediately.
The difference between a cold and the flu
Many people confuse the flu with a cold. Here are the key differences:
| Cold | Flu | |
|---|---|---|
| Onset | Gradual over 1–3 days | Sudden, within hours |
| Fever | Low or none | High (102–104°F), 3–5 days |
| Body aches | Rare | Common and pronounced |
| Fatigue | Mild | Severe, can last weeks |
| Runny/stuffy nose | Main symptom | Less prominent |
| Cough | Mild, productive | Dry, irritating |
| Duration | 7–10 days | Fever 3–5 days, cough/fatigue up to 2–3 weeks |
It is not always easy to tell the difference between a cold and the flu. If you are unsure, look at the child's overall condition — a child with the flu is usually noticeably sicker than with an ordinary cold.
Treatment of flu in children
The flu is a viral illness, and antibiotics do not help. Treatment is about relieving symptoms while the immune system fights the virus.
Fever and pain
- Acetaminophen (Tylenol) — for fever and pain, follow age-appropriate dosing
- Ibuprofen (Advil, Motrin) — can be used in children over 6 months as an addition or alternative to acetaminophen
- It is not necessary to treat all fever — give medication when the child is clearly uncomfortable
Fluids and food
- Offer frequent fluids — water, breast milk, or formula. Older children can have warm drinks with honey (over 12 months)
- Do not force the child to eat — loss of appetite is normal. Offer light foods such as yogurt, soup, or toast
- Popsicles — can be popular and provide fluids at the same time
Rest and comfort
- Rest — the child needs plenty of rest, but does not have to stay in bed the entire time
- Fresh air — a short time outside in fresh air can do good if the child feels up to it
- Elevated head — can ease breathing for children with a stuffy nose
- Saline nasal drops — help with a stuffy nose, especially important for babies who breathe through their nose
On room temperature: Keep the room cool (around 65–68°F / 18–20°C) and well ventilated. A child with a fever does not need to be bundled up in extra clothes or blankets — this can make the fever worse.
Antiviral medications
In special cases, the doctor may prescribe antiviral medications (oseltamivir/Tamiflu) for children in high-risk groups. These work best when started within 48 hours of symptom onset.
Possible complications
Most children recover from the flu without problems, but some may develop complications:
- Ear infection — the most common complication in young children
- Pneumonia — can be viral or bacterial (secondary infection)
- Bronchitis — cough and congestion in the airways
- Dehydration — especially in young children who refuse to drink
- Worsening of chronic illness — asthma, diabetes, and other chronic conditions
Children in the high-risk group for serious flu:
- Babies under 6 months
- Children with chronic lung or heart disease
- Children with weakened immune systems
- Children with diabetes or other metabolic conditions
When should you see a doctor?
Call your pediatrician or after-hours nurse line if the child:
- Is under 3 months with a fever above 100.4°F (38°C)
- Has a fever lasting more than 5 days
- Has fast or labored breathing
- Will not drink or has dry diapers (signs of dehydration)
- Is very lethargic and difficult to engage
- Gets better and then suddenly gets worse again (may indicate a bacterial complication)
- Has a chronic illness and develops flu symptoms
Call emergency services immediately if the child has severe breathing difficulties, blue-tinged skin around the lips, is difficult to wake, or shows signs of serious dehydration (no tears, sunken eyes, limp).
Flu vaccine for children
The Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) recommend annual flu vaccination for all children 6 months and older. Children at higher risk who particularly benefit from vaccination include:
- Children with chronic lung or heart disease (including severe asthma)
- Children with diabetes or other metabolic conditions
- Children with weakened immune systems
- Children with chronic kidney disease
Vaccination in practice
- The vaccine is usually given from October, before flu season begins
- Children under 9 years being vaccinated for the first time need two doses at least 4 weeks apart
- The vaccine must be given every year because the influenza virus changes
- Children under 6 months cannot be vaccinated — here it is especially important that parents and siblings get vaccinated
Talk to your pediatrician about whether your child should be vaccinated against flu. For children in high-risk groups, vaccination is particularly important and may be covered by insurance.
Preventing the spread of infection
Good hygiene practices reduce the risk of flu transmission:
- Handwashing — wash hands frequently with soap and water, especially after coughing and sneezing
- Cough into elbow — teach your child to cough and sneeze into the crook of the elbow, not into hands
- Avoid touching the face — avoid touching eyes, nose, and mouth
- Keep sick children home — the child should stay home from daycare until they have been fever-free for 24 hours without fever-reducing medication
- Clean surfaces — wash toys, door handles, and other frequently touched surfaces
Frequently asked questions
How long does the flu last in children?
Fever and the worst symptoms usually last 3–5 days. Cough and fatigue can linger for 2–3 weeks, however. The child may feel run-down longer than adults.
Can babies under 1 year get the flu?
Yes, and babies are in the high-risk group for a serious course. Babies under 6 months cannot be vaccinated, so it is important that people around the baby get vaccinated and practice good hand hygiene.
Is it dangerous to give ibuprofen to a child with the flu?
No, ibuprofen can be used for children over 6 months with the flu. Note that ibuprofen should not be used for chickenpox. Acetaminophen is always a safe first choice.
Can the child go to daycare with the flu?
The child should be kept home as long as they have a fever. Most daycare centers require the child to be fever-free for at least 24 hours without fever-reducing medication before returning.
Read more
Sources
- Centers for Disease Control and Prevention (CDC) — Influenza (Flu)
- American Academy of Pediatrics (AAP) — Influenza guidelines
- WHO — Influenza (Seasonal) fact sheet