What is Influenza

Influenza is an infection that affects the breathing passages (also known as 'airways'). It is caused by the influenza virus. There are several forms of the virus and each can change over time. Each year scientists try to work out which form of the influenza virus is most likely to be the cause of the year's epidemic.

Many people think of influenza as 'the flu' and use this term for common illnesses like head colds. Influenza is much more serious.

In Australia, influenza causes as many as 20-40,000 hospital admissions, 1.5 million days off work and 1,500 deaths each year. And it is not only elderly people who are affected by influenza. People younger than 65 years make up around 68% of these hospital admissions.

As well as being a very unpleasant illness, influenza costs Australia a great deal in doctor visits, hospital stays and days off work.

The Symptoms of Influenza

The symptoms are quite different to the common cold or other respiratory infections. They can include: fever, headache, muscular aches, sore throat, dry cough. These often begin suddenly and develop quickly.

Influenza is much more than a cough and cold. It usually requires 2-4 days in bed. Full recovery can take up to 3-4 weeks.

How Does Influenza Spread?

Influenza is generally spread by the coughs and sneezes of an infected person. The infection starts in the upper breathing passages - the nose and throat. 

If the virus spreads further down into the lungs, this can result in bronchitis and pneumonia.

Who is at Risk

While almost anyone can get influenza, there are a number of 'high risk' groups. People with asthma and other lung diseases are especially vulnerable. Viral infections can lead to increased asthma symptoms and other serious complications like pneumonia (inflamed lungs).

If you are over 60 and have a chronic (long-term) lung disease, your risk of being hospitalised with pneumonia is up to seven times higher than normal.

These complications can cause death, especially in older people. Young people also die from influenza. The solution is to prevent influenza infections in people at risk.

How can Influenza be prevented

Vaccination is the only effective way to prevent influenza. Doctors strongly recommend vaccination every year for adults and children with severe asthma.

The influenza vaccine takes about 14 days to provide its greatest protection. Talk to your doctor about getting vaccinated in autumn, before the influenza season arrives.

People aged 65 and over receive the vaccine free.

Vaccination for People with Asthma

Influenza vaccination is currently recommended for all who want it. It is particularly recommended for

• children 6 months and older with severe asthma (frequent asthma attacks or regular hospital admissions)

• teenagers with severe asthma

• adults with severe asthma

• pregnant women with severe asthma or women with asthma who anticipate being pregnant through the winter. In this case, it is wise to be vaccinated before the pregnancy.

Note: people with proven egg allergy should not have the influenza vaccine. It occasionally causes a reaction. If you suspect you have egg allergy, consult your doctor.

What about Side Effects?

Many people believe that the influenza vaccine can cause flu-like symptoms. However, as the vaccine is made up of inactive (dead) virus pieces, it cannot cause influenza. You may have a sore arm after the injection, but that is all. 

For Further Information

Speak to your GP or pharmacist

Contact your local Asthma Foundation on 1800 645 130.

Content Updated May 2004