Usual symptoms

• People with influenza may feel tired or lacking in energy (fatigue) and get a headache, a cough, chills, muscle aches (myalgia), a runny nose and sneezing.
   

Rare symptoms

• People with influenza sometimes get swollen airways (acute bronchitis), swelling in their voice box and windpipe that causes a bark-like cough (croup), ear infection that causes ear ache (otitis media) and infected lungs (pneumonia).
   

Very rare symptoms

• Very rarely, people with influenza can get swelling (inflammation) in their heart muscle (myocarditis), the lining of their heart (pericarditis) or their brain (encephalitis). They can also get swelling in their liver and brain (Reye’s syndrome).¹
• Very rarely, people can die from influenza. Each year in Australia, influenza is reported to cause an average of approximately 400 deaths.² Because this number is hard to calculate accurately, the true number is likely higher.

An influenza vaccine is the best way to protect your adolescent against influenza.

As well as protecting your adolescent from getting sick, an annual influenza vaccination helps protect the people around them. If you don’t catch influenza, you can’t spread influenza. This community protection is especially important for vulnerable people, like babies aged under 6 months, who can’t get the vaccine; older people (aged 65 years and over); and people with low immunity.

Influenza vaccines protect your adolescent against several types (strains) of influenza virus. The strains of influenza the vaccine protects against may change each year, depending on which strains are likely to be circulating.

From 2026, adolescents can receive a flu vaccine either by an injection in the arm or 2 quick sprays up the nose. You can find more information about the nasal flu vaccine on the National Centre for Immunisation Research and Surveillance website.

It is recommended that all people aged 6 months and over get an influenza vaccine every year. 

In Australia, the best time to get an influenza vaccine is in April or May, before the flu season, which is usually June–September.³ They can be vaccinated later in the season, too.

Your adolescent can get an influenza vaccine either on its own or at the same time as their other age-specific vaccinations.

Some adolescents with certain health or medical risk conditions (including asthma and heart conditions) or those who identify as Aboriginal and Torres Strait Islander may qualify for a free flu vaccine. Speak with your doctor, nurse or community health worker to see if your adolescent qualifies.  

Even if your adolescent is mildly unwell on the day of their appointment (this means no fever and a temperature under 38.5°C), they can still receive the vaccine.⁴

The influenza vaccine protects against 3 types (or strains) of the influenza virus. It works by ‘training’ your adolescent’s immune system to recognise and get rid of the influenza virus. When their immune system detects the antigens in the vaccine, it produces proteins called antibodies. These antibodies are like soldiers that recognise and remember the influenza type. If your adolescent is ever exposed to the real influenza virus, their immune system will recognise it quickly and fight it off using the antibodies it created after vaccination.⁵

Your body usually starts producing antibodies around one or 2 weeks after you have the vaccine.

Influenza vaccines given as an injection in the arm do not contain any blood products and are not ‘live’ vaccines. The inactivated antigens cannot replicate themselves or cause disease.  

The nasal flu vaccine is a weakened (attenuated) live vaccine. It contains a weakened live virus, which cannot give someone with a strong immune system the flu. It is given via a quick spray into each nostril and is absorbed rapidly. 

Overall, influenza vaccination is the most effective way to protect your adolescent against the virus; but the effectiveness of influenza vaccines can vary depending on which strains of the virus are present in the community.

Each year, the Australian Influenza Vaccine Committee follows the recommendations of the World Health Organization to decide which influenza strains should be included in the vaccine to provide the best protection.

It’s important for adolescents to get an influenza vaccine every year to ensure they are vaccinated against the strains of the virus that are likely to be circulating that season.  

Research has shown influenza vaccination can reduce a child or adolescent’s (aged 1–15 years) chance of catching influenza by 70–91%.⁶

No, there is no risk your adolescent will catch influenza from a flu vaccine. Occasionally, adolescents receiving any type of flu vaccine may develop a runny or blocked nose, headache and tiredness, but they fully recover over a few days.  

Flu vaccines given as an injection in the arm do not contain the live virus that causes the disease.

The nasal flu vaccine is a live vaccine that contains a weakened (attenuated) version of the influenza virus. It contains weakened viruses that grow only in very specific cold conditions.

In children with strong immune systems, these weakened viruses can only copy themselves in the nose, but not in the rest of the body. This means the nasal flu vaccine cannot cause real influenza disease in children with strong immune systems. 

Adolescents with cancer or who have very weakened immune systems should not have live vaccines like the nasal spray flu vaccine because they can become very unwell. Your immunisation provider will screen for these conditions before giving your adolescent their flu vaccine. The flu vaccine given as an injection in the arm can be provided instead. 

• It is common for people who have an influenza vaccine given as an injection in the arm to experience swelling, redness and pain where the injection was given. This can last one or 2 days after receiving the vaccine.⁶
• Side effects after the nasal flu vaccine are similar to the flu vaccine given as an injection in the arm. However nasal symptoms like runny nose or congestion can occur more often with the nasal spray flu vaccine.⁷
• Less than 15% of people who have an influenza vaccine given as an injection in the arm get a fever, headache, tiredness or lack of energy (fatigue) or muscle aches (myalgia) that last one or two days.⁶ 

• About 0.0001% of people (1 out of every 1,000,000) who get an influenza vaccine have a severe allergic reaction (anaphylaxis).⁸ This reaction usually happens within 15 minutes of getting the vaccine and can be treated with an injection of adrenaline. People who have this reaction usually recover quickly and don’t experience any long-term effects.⁹
• Less than 0.0001% of people (1 out of every 1,000,000) who get an influenza vaccine get Guillain-Barré syndrome, a rare disorder where a person’s immune system damages their peripheral nerve cells.⁴ While many people recover fully, others may continue to experience persistent symptoms.^10,11

The most important thing you can do to protect your adolescent is ensure they get a seasonal influenza vaccine every year, because the types of influenza viruses circulating often change from year to year and protection from vaccination generally lasts less than 12 months.

You can read some answers to common questions here.

If you still have some questions about vaccinations for your adolescent, write them down and make an appointment with your nurse, your doctor or your health worker so you can ask them.