Health conditions

Influenza (flu)

  • Influenza (flu) is a common, highly contagious virus that affects the respiratory system.
  • The virus can cause a mild to serious illness and even death in young children, older adults and vulnerable people.
  • Getting the influenza vaccine is your best protection against influenza.

Influenza is not the same as the common cold.

There are two basic types of influenza – A and B – that cause illness in people.

These are called the seasonal influenza viruses, as they emerge each year, mostly in the winter months.

Terms explained

Influenza season – this is an annually-recurring time period characterised by the prevalence of outbreaks of influenza. The season occurs during the colder months of the year.

Influenza pandemic – this is a global outbreak of influenza. It occurs when a new strain of the flu virus, against which people have little or no immunity, spreads quickly from person-to-person. Find out more about influenza pandemics.

How do you get influenza?

Influenza virus is spread through the air when someone coughs, sneezes or talks.

You can also catch the influenza from touching a contaminated surface with the influenza virus on it, and then touching your mouth, eyes or nose.

Notifiable disease

Influenza is a notifiable disease. This means doctors, hospitals and laboratories must inform the Department of Health of your diagnosis. This allows the Department to monitor the extent of influenza cases in our community and to take necessary action in some situations, for example outbreaks in day care or aged care centres. Notification is confidential.

Who is most at risk?

Influenza can be a serious illness for older people, young children, pregnant women, or people of any age who have a chronic medical condition, such as heart disease or diabetes.

Most influenza cases occur in children less than 4, pregnant women and in people over 60.

If you are in one of the groups above, you:

  • are strongly encouraged to get vaccinated against influenza
  • should seek medical attention if you develop influenza-like symptoms.

Pregnant women

If you are pregnant you are at an increased risk of developing serious health complications from the influenza such as pneumonia, compared to women who are not pregnant.

Babies and young children

Anyone can get the influenza, but rates of infection and hospitalisation are highest among young children and people over 65.

Learn about the influenza vaccine and children.

What are the signs and symptoms?

Most healthy children and adults only have minor symptoms.

Typical symptoms in adults can include:

  • sudden onset of fever
  • headache
  • sore throat
  • runny nose
  • cough
  • fatigue (tiredness)
  • general aches and pains
  • nose, throat and lung congestion.

Most people recover within a few days, but in some people with existing medical conditions more serious infections can occur such as pneumonia or inflammation of the lungs, resulting in a much longer illness.

Influenza symptoms in children

Influenza symptoms in children can include symptoms which are more uncommon in adults, such as:

  • nausea (feeling sick)
  • vomiting
  • diarrhoea.

You should see your doctor urgently if your child’s health worsens or you notice new symptoms developing.

Signs to watch for include:

  • fast breathing or difficulty breathing
  • skin starts to turn blue
  • refusal to eat or drink
  • not waking up properly or not interacting
  • being extremely irritable, and not wanting to be held
  • fever and a rash
  • persistent vomiting.

People at high risk

It’s important for people at higher risk of developing a serious illness or health complications from influenza to see a doctor immediately for a medical diagnosis.

If you only have mild symptoms, you should stay at home until you are feeling better.

See a doctor if you start experiencing the following symptoms:

  • fast breathing or difficulty breathing
  • skin starting to turn blue
  • pain or pressure in the chest or abdomen
  • sudden dizziness
  • confusion
  • a rash
  • persistent vomiting.

In some cases the influenza-like symptoms can improve but then return with a fever and a worse cough.

What is the difference between the influenza and a cold?

What is the difference between influenza and a cold?

Although influenza symptoms are similar to a cold symptoms (especially in children), the influenza virus is more incapacitating and lasts much longer than a cold.

Table: Understanding the differences between cold and flu symptoms
Symptom Influenza Cold
Headache and aches and pains Common
May be less severe
Fatigue and weakness Common
Last days
Usually mild
Runny/stuffy nose Uncommon Common
Sore throat Uncommon Common
Cough Common
Dry or moist
How do you treat the influenza?

Usually someone with influenza will recover naturally within 2 to 7 days.

If you have mild symptoms and are not at increased risk of developing severe illness from influenza, you should stay at home and rest until you are well.

The recommended treatment for mild to moderate influenza is to:

  • Take paracetamol to help reduce fever and head and muscle aches.
  • Get plenty of rest.
  • Drink plenty of fluids.
  • Eat healthy food.

Decongestants and other cold remedies will not help and antibiotics do not treat influenza unless you have secondary bacterial infection (which must be diagnosed by a doctor).

Antiviral medication can help to manage your illness but only if you are treated early, within 12 to 48 hours of showing influenza symptoms. Influenza is not usually diagnosed within this period, so it is not commonly used (except in special circumstances).

While you have influenza

  • Stay home from school or work and avoid contact with other people.
  • Wash your hands often, especially after coughing, sneezing or blowing your nose and before you prepare any food.
  • Use disposable tissues and immediately throw used tissues in the bin.
  • Cover your mouth when you cough or sneeze.
How can influenza be prevented?

The best way to prevent catching influenza is to have the influenza vaccination.

Follow these tips to help avoid, or to stop yourself giving it to others:

  • cover coughs: cover coughs and sneezes with a tissue or use your inner elbow
  • throw used tissues in the bin
  • wash hands: wash your hands often with soap and water or use antibacterial hand sanitisers, especially after you cough
  • clean surfaces: clean surfaces and objects such as doorknobs, keyboards and phones regularly
  • Stay at home: If you have influenza, stay home from work or school and limit your contact with other people
  • try to avoid close contact with people who have influenza symptoms.

Learn more about hand hygiene and protecting yourself from influenza.

Read more about preventing flu and other respiratory infections.

Is there an influenza vaccine?

Yes. The influenza vaccine protects people against the influenza virus and the common complications of this infection. Each year a new vaccine containing the 3 most common strains of circulating influenza viruses is produced.

The influenza vaccine is available in metropolitan and country WA from immunisation providers including GP clinics, community health clinics and Aboriginal Medical Services.

Find out more about influenza vaccination. For further information, contact your GP or immunisation provider.

Who should be immunised against influenza?

Everyone is encouraged to get the influenza vaccine.

Some groups of people are at higher risk of serious complications from influenza and are strongly recommended to get immunised. Many of these high risk groups are eligible to receive free government-funded influenza vaccinations.

Find out more about influenza vaccination.

For further information, contact your GP or immunisation provider

Where to get help


  • Influenza is more severe and lasts longer than a cold.
  • It is highly contagious and spread by coughing, sneezing and touching.
  • Influenza can lead to serious health complications which can be fatal.
  • A vaccination against influenza can help protect you.

Last reviewed: 10-05-2019
Public Health

This publication is provided for education and information purposes only. It is not a substitute for professional advice. Information about a service, product or treatment does not imply endorsement and is not intended to replace professional advice. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified professional for answers to their questions.

Where can I get my vaccine?