Baby Flu: When to Call and What to Do

A parent holds an alert infant on a sofa. — Notice whether your baby stays alert and responsive when awake.

Children under 5, especially those under 2, have a higher risk of serious flu complications, so call your baby's clinician promptly when flu is suspected.

SUMMARY

If your baby is under 12 weeks with any fever, or has trouble breathing at any age, get urgent medical care.

Ask your baby's clinician early about prescription flu antivirals, which work best within 2 days of symptoms starting.

What symptoms should I notice?

Flu can bring fever, cough and a runny or stuffy nose; some children also vomit or have diarrhea.

A baby can have flu without a fever.

A parent checks an awake baby with a forehead thermometer. — Flu can happen without fever, so do not rely on temperature alone.

Call early when flu is suspected

A clinician may examine your baby and decide whether flu testing is needed.

Prescription flu antivirals work best when started within 2 days of symptoms, and your baby's clinician decides whether to prescribe them.

Some children can still benefit from antiviral treatment after 2 days, especially when their risk is high or illness is severe.

A father holds his baby while speaking by phone. — An early call allows a clinician to consider flu testing and antiviral treatment.

Go now for these warning signs

For a baby younger than 12 weeks, any fever needs urgent medical care.

Get urgent medical care for fast or difficult breathing, ribs pulling in with each breath, or blue lips or face.

No urine for 8 hours, a dry mouth or no tears while crying can signal dehydration and needs urgent medical care.

Seek urgent medical care if your baby is not alert or responsive while awake, or has a seizure.

A fever or cough that improves and then returns or worsens also needs urgent medical care.

A clinician speaks with a parent holding a baby. — A fever or cough that improves and returns needs urgent care.

Comfort and medicines while arranging care

While arranging care, let your baby rest and offer milk feeds for fluids.

Never give aspirin to a child with suspected or confirmed flu.

Ask your baby's clinician about fever medicine and age- and weight-appropriate doses; ibuprofen is for children 6 months or older and must not be given if they are dehydrated or vomiting continuously.

Antibiotics do not treat the influenza virus, though a clinician may use them for a separate bacterial complication.

A parent bottle-feeds an awake baby. — Milk feeds can provide fluids before the visit.

Protecting your baby before flu arrives

Babies younger than 6 months cannot receive a flu vaccine; in the US, children should get one each year from 6 months onward.

Under CDC guidance, a baby receiving a first flu vaccine at 6–11 months needs a second dose at least 4 weeks later.

Under CDC guidance, caregivers and household members aged 6 months or older should also receive a flu vaccine each year to reduce the chance of passing flu to the baby.

In England, NHS flu vaccination is offered from 6 months to children with certain long-term conditions.

If a caregiver develops flu symptoms, limit close contact when possible and wash hands before feeding or other close care.

A parent washes hands while a baby rests in a bassinet. — Wash hands before feeding or other close care to reduce flu spread.

Frequently asked questions

Must we wait for a positive flu test before discussing treatment?

A clinician may prescribe flu antivirals for suspected flu without waiting for a positive test.

Can a baby with flu continue breast milk?

A baby with flu can continue breastfeeding or receive expressed breast milk.