Flu in kids: symptoms, treatment, and when to worry

How is the flu different from a cold?

Flu tends to hit all at once, while a cold builds gradually over a day or two. Signs that point to flu:

• Sudden fever, often 101–104°F, sometimes with chills
• Body aches and headache
• Dry cough and sore throat
• Marked tiredness — the child wants to lie still
• Vomiting or diarrhea, which happen more often in children than in adults

A cold, by contrast, usually means a stuffy or runny nose and sneezing, with little or no fever and near-normal energy. RSV and COVID can overlap with flu, especially in younger children — one more reason a visit helps when you are not sure which illness you are dealing with.

How long does the flu last in kids?

For most healthy children, fever lasts about 3 to 5 days (sometimes up to a week), the worst symptoms are in the first few days, and cough and tiredness can linger for 2 weeks or more after the child is clearly improving. Children are contagious from about a day before symptoms start until at least 5 to 7 days after — and younger children can spread flu longer.

Your child can return to school or daycare once they have been fever-free for a full 24 hours without fever medicine and are feeling up to it.

When should you contact a pediatrician promptly?

• Your baby is younger than 3 months and has a temperature of 100.4°F (38°C) or higher.
• Your child is younger than 5 — especially younger than 2 — or has asthma, diabetes, a heart or lung condition, or a weakened immune system. These children benefit most from early antiviral treatment.
• The fever lasts more than 5 days, or goes away and then comes back — that pattern can mean a second infection, such as an ear infection or pneumonia.
• Symptoms were improving and then suddenly get worse.
• Your child is not drinking well or is urinating much less than usual.

Can telemedicine help with the flu?

Yes — and timing is the reason. On a video visit a pediatrician can assess your child's breathing, alertness, and hydration, review the symptoms and medical history, and decide whether antiviral medicine is appropriate. Because antivirals work best within 48 hours of symptoms starting, a same-day online visit can be the difference between medicine that helps and medicine that no longer does.

One visit handles the whole episode: prescriptions are sent to your pharmacy when one is appropriate, school and daycare notes for your child and work notes for you are provided, your child's visit records are available online through CarePatron, and follow-up visits within a week of the original visit are included in the initial consult fee.

Telemedicine cannot do everything: it cannot run a flu test or listen to the lungs. If your child needs a hands-on examination or testing, we will tell you clearly and direct you to in-person care. Telemedicine never replaces emergency care.

What can parents do at home?

• Offer fluids regularly — small, frequent sips of water, oral rehydration drinks, or popsicles — and watch that your child keeps urinating.
• Let your child rest, and keep them home from school or daycare.
• Use fever medicine for comfort, dosed by weight: acetaminophen (Tylenol) or ibuprofen (Advil or Motrin), following the package directions for your child's weight.
• Never give aspirin to a child or teenager younger than 16 with flu or another viral illness — it is linked to a rare but serious condition called Reye's syndrome.
• For cough, honey can help children older than 1 year. Ask your pediatrician before using over-the-counter cough and cold medicines in young children.
• Write down temperatures, medicine times, and fluid intake to share at the visit.

Preventing flu: the yearly flu shot

The flu vaccine is recommended every year for everyone 6 months and older. It lowers your child's chance of catching flu and makes the illness milder and far less likely to require hospital care if they do. If your family has not had it yet this season, it is not too late — protection still helps as long as flu is circulating.