Influenza (or ‘the flu’) is caused by three types of influenza virus – A, B and C that infect the respiratory system.  Influenza is contagious and is spread by coughing, sneezing and direct contact with an infected person or by touching a contaminated surface. Extended periods in an enclosed poorly ventilated space with an infected person increases the chances of getting influenza.  You can be infectious around a day before symptoms appear.

Influenza illness can include any or all of these symptoms: fever, muscle aches, headache, lack of energy, dry cough, sore throat, and possibly a runny nose. The fever and body aches can last 3-5 days and the cough and lack of energy may last for two or more weeks.

Although people with underlying health conditions are most at risk from influenza associated complications, previously healthy people can still become seriously ill and even die.

Influenza continues to be a major threat to public health worldwide because of its ability to spread rapidly through populations.  Anyone from the age of 6 months on can be vaccinated against influenza.  The vaccine is fully funded by PHARMAC for certain groups of people who are considered to be at greater risk of complications from influenza. The vaccine is recommended (although not funded) particularly for those who are in close contact with people at high-risk of complications to reduce the risk of spread of the virus.

Influenza, commonly called the flu, can be a serious illness that is sometimes fatal. Infection with the influenza virus may lead to a stay in hospital for any age group but particularly if you are elderly or have an ongoing medical condition. Influenza can make an existing medical condition, such as asthma or diabetes, a lot worse.

Even if you do not end up in hospital, influenza can keep you in bed for a week or more, preventing you from doing work,sport or just about anything that requires leaving the house

Influenza is different from a cold virus.  A cold virus only affects the nose, throat and the upper chest and lasts for a few days, whereas influenza can be a serious illness that affects the whole body and can last up to a week or more.

No. You cannot get influenza from the vaccine, as it does not contain any live viruses. Some people may experience mild reactions such as muscle aches or headaches for a short time after immunisation, and they may think this is the flu – but it’s not.


People eligible for a free influenza immunisation

Eligible people can get a free vaccination from their family doctor/general practice, and it is usually the practice nurse who administers the vaccine. 

Many community pharmacies provide free influenza vaccinations to:

  • individuals aged 13 years and older
  • pregnant women (any trimester) 

People who are not eligible to receive a free influenza immunisation

Influenza immunisation is available from:

Please contact your provider regarding the cost of influenza immunisation.

Yes.  The vaccine can be given to children aged 6 months and over. The influenza vaccine is free for children aged four years and under who have had a stay in hospital for asthma or other breathing problems or have a medical condition that increase the risk of acquiring influenza or developing complications from influenza. For more information, talk to your doctor or nurse.

The World Health Organization (WHO) takes influenza very seriously.  Each year the WHO Information Surveillance Network studies the different strains of influenza and monitors their movements around the globe.  They then decide which strains of the virus are likely to emerge in different parts of the world and provide advice for what strains influenza vaccines should include.

The influenza virus has many strains.  The World Health Organization monitors the different influenza strains and their movements around the world. They then decide what strains are likely to circulate in the Southern Hemishphere and recommend the influenza strains to be included in the influenza vaccine.  

The influenza strains included in the 2021 influenza vaccines are:

  • A/Victoria/2570/2019 (H1N1)pdm09-like virus
  • A/Hong Kong/2671/2019 (H3N2)-like virus
  • B/Washington/02/2019-like virus
  • B/Phuket/3073/2013-like virus

The vaccine cannot give you influenza as it only contains fragments of the virus. The vaccine stimulates the immune system to make cells that protect against circulating viruses. Most people have no reaction to the vaccine. Occasionally the site where the vaccination was given is red or sore for a day or two.  Some people may feel unwell for a day or two. These are normal responses to the immunisation.

It takes up to two weeks after immunisation for the body to start developing protection against influenza. When the influenza strains in the vaccine are a good match to the influenza strains circulating in the community, around  half to two-thirds of healthy adults aged under 65 years of age who received the vaccine will be protected against influenza. The immunisation can also protect almost two-thirds of these adults from being unwell enough with influenza to need hospital care. 

Influenza immunisation doesn’t protect against the common cold or other viruses and diseases in circulation. Influenza immunisation does not protect against coronavirus infections.

It takes up to two weeks for the influenza immunisation to start providing protection.

No.  The influenza vaccines do not contain thiomersal, mercury or any other preservative.

Women who are pregnant, children and adults with chronic health conditions, and adults aged 65 years or older should visit their doctor as soon as they think they have influenza. Early treatment with antiviral medication may make the illness less severe. 

Other people may be able to manage their influenza symptoms without visiting their doctor. However, people who are worried about how serious their symptoms are, people who haven't improved after two weeks and those who were starting to feel better and then suddenly feel worse or develop a new symptom should also visit their doctor.

Use this link to visit the  Health Navigator NZ influenza webpage for more information about when infants, children and adults with influenza should visit a doctor.