Influenza factsheet

Introduction

Influenza, also called the flu, is a virus that affects the nose, throat, and lungs.

It spreads easily through fluids, including:

  • saliva
  • snot
  • droplets in the air from coughing or sneezing.

Children are more likely to catch influenza during the winter months. 

 Signs and symptoms

Influenza can affect each child differently, depending on their health and the type of virus.

Children can spread the virus before they show symptoms and while they are unwell.

Symptoms can range from mild to severe.

Common symptoms can include:

  • fever
  • aches and pains
  • headache
  • cough or noisy breathing
  • sore throat
  • runny nose
  • tiredness
  • nausea and vomiting
  • diarrhoea – loose, watery poo that is difficult to control.

More serious symptoms can include:

  • not wanting to eat or drink
  • dehydration
  • trouble breathing
  • high fever that won’t go down
  • being very sleepy or not responding.

Go to your nearest emergency department if your child has severe symptoms, including:

See your doctor if your child has influenza and has a long-term health condition or is at higher risk of getting very sick.

Diagnosis

Your doctor can diagnose influenza by:

  • checking your child’s symptoms
  • doing a swab of the nose or throat.

Treatment

Most children with mild influenza can be treated at home and feel better in about a week.

To help your child recover:

Influenza is a viral infection; it cannot be treated with antibiotics.

Antiviral medicine like Tamiflu is usually not needed for otherwise healthy children.

Do not give aspirin to children as it can cause serious side effects.

 Management

Influenza (flu) vaccine

The best way to prevent influenza or reduce how sick your child gets is to have the flu vaccine every year.

The virus changes each year, so a new vaccine is needed each flu season.

In Australia, the flu season is from July to October.

Children over 6 months old can have the flu vaccine.

Talk to your doctor if your child has a medical condition or an egg allergy.

Common side effects of the flu vaccine include:

  • a sore arm
  • redness
  • fever
  • aches and pains.

These should go away after a few days and can be managed with rest, fluids, and over-the-counter pain relief.

Preventing the spread of influenza

Teach your child good hygiene to help stop the spread of influenza. This includes:

  • coughing or sneezing into a tissue, elbow or hand
  • washing hands often with soap
  • wearing a mask when unwell
  • not sharing water bottles or eating utensils.

Resources and more information

SKAI - Sharing Knowledge About Immunisation

title
Sharing Knowledge About Immunisation (SKAI)

Biography
SKAI is home to credible information about the vaccines recommended in Australia, and the diseases they can prevent.
Related Links
National Centre for Immunisation Research and Surveillance (NCIRS)

title
National Centre for Immunisation Research and Surveillance (NCIRS)

Biography
Influenza immunisation FAQs, fact sheets, publications and data to assist health care providers and the public with the latest available information.
Related Links

Disclaimer

This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2025


This factsheet was produced with support from John Hunter Children's Hospital.