Influenza factsheet


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

Influenza spreads quickly through contact with fluids, including: 

  • saliva in the mouth
  • snot in the nose
  • fluid droplets in the air from coughing and sneezing. 

Your child is more likely to get influenza during winter, and symptoms can range from mild to severe.

 Signs and symptoms

Influenza can affect children differently depending on how healthy they are and their specific type of influenza virus. 

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

Symptoms can include:

  • fever
  • general aches and pains
  • headache
  • cough or noisy breathing
  • sore throat
  • runny nose
  • low energy
  • nausea and vomiting
  • diarrhoea, or loose and watery poo.

More severe symptoms can include:

  • not wanting to eat or drink
  • dehydration from losing fluid faster than taking it in
  • difficulty breathing
  • high fever that does not go down
  • not responding to people or the environment.

Go to your nearest emergency department if your child has:

  • chest pain
  • breathing difficulties
  • dizziness or confusion
  • severe vomiting
  • dehydration
  • severe symptoms that continue to get worse.

See your local doctor as soon as possible if your child has influenza and a chronic condition or is at risk of severe illness.


Your local doctor can diagnose influenza based on their symptoms and the results from a nose and throat swab.


Mild influenza can be treated at home; most children will recover in about a week.

You can help your child recover from influenza at home by making sure they:

  • rest
  • drink fluids
  • manage fever and pain with over-the-counter medication like paracetamol or ibuprofen.

Because influenza is a viral infection, it cannot be treated with antibiotics.

Antiviral medications like Tamiflu are generally not given to children who are otherwise fit and healthy because they do not make a big enough difference to the length of the illness. 

Do not give aspirin to your child if they have influenza, as this can lead to serious side effects.


Influenza vaccine

The best way to prevent influenza and reduce the severity of the illness is to get the influenza vaccine every year.

The influenza virus changes or mutates slightly each year, so your family will need a new and updated flu vaccine at the beginning of each season. 

In Australia, the influenza season is the winter months of July to October.

Children can get the influenza vaccine if they are over 6 months old.

Speak to your child’s doctor about the influenza vaccine if you are concerned that your child has ongoing medical issues or an egg allergy.

The influenza vaccine has some common side effects, including:

  • slight pain where the needle was given
  • redness
  • high temperature
  • aches and pains.

These side-effects should stop after a few days and can be treated with:

  • rest
  • fluids
  • over the counter pain relief like paracetamol or ibuprofen.

Preventing the spread of influenza

Teaching your child good hygiene habits is the best way to stop the spread of influenza.

Good hygiene habits can include:

  • coughing and sneezing into their hand, tissue, or sleeve
  • regular hand washing with soap
  • wearing a mask when unwell
  • not sharing things like water bottles and eating utensils.

Resources and more information

SKAI - Sharing Knowledge About Immunisation

Sharing Knowledge About Immunisation (SKAI)

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)

National Centre for Immunisation Research and Surveillance (NCIRS)

Influenza immunisation FAQs, fact sheets, publications and data to assist health care providers and the public with the latest available information.
Related Links
Last updated Monday 11th December 2023


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 2024