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Feeling sick? Why fighting the flu is a constant battle, year in and year out.

Ever wondered why a flu shot is recommended every year?

The influenza virus is continually changing, that’s why it’s important to be vaccinated every year. Flu vaccines are developed based on research from influenza centres in over 100 countries, who monitor which flu viruses are making people sick, how they spread and also how well the previous season’s vaccine worked1

While it’s generally recognised that influenza activity in the northern hemisphere is similar to that in the southern hemisphere,2 these viruses can change abruptly and at different times of the year so the vaccines are adjusted for the different hemispheres3.

This year, it is recommended by the Australian Influenza Vaccine Committee that trivalent (three strain) vaccines for use in the 2015 influenza season (southern hemisphere winter) in Australia contain the following strains4:

·         A/California/7/2009 (H1N1) -like virus (same strain as last year)

·         A/Switzerland/9715293/2013 (H3N2)-like virus (different strain to last year)

·         B/Phuket/3073/2013-like virus (different strain to last year)

Quadrivalent (four strain) vaccines for use in the 2015 influenza season (southern hemisphere winter) are recommended to contain:

·         A/California/07/2009 (H1N1)pdm09-like virus

·         A/Switzerland/9715293/2013 (H3N2)-like virus

·         B/Phuket/3073/2013-like virus (Yamagata lineage)

·         B/Brisbane/60/2008-like virus (Victoria lineage)

Another reason why it’s important to be vaccinated EVERY year is because immunity to influenza declines over the course of a year after vaccination or infection, particularly in the elderly5. This weakening immunity can be due to several factors such as age or health situation, or even the antigen used in the vaccine.6

While the flu shot is expected to cover the most common flu strains, other types of influenza viruses can be in circulation. Unfortunately some people may still fall ill with influenza due to the prevalence of other virus strains not covered in the vaccine for the season 7.

Remember to get vaccinated before winter starts.

There are a couple of reasons for this:

  1. It takes about two weeks after vaccination for antibodies to develop in the body that provide protection against the flu so it’s usually recommended to receive the vaccine in autumn in Australia.8
  2. Influenza seasons are unpredictable.Experts warn this year the flu has struck early, with over 4500 cases in 2015 before the winter months have even begun.10
  3. Even if you received a flu shot towards the end of the last flu season, you should still be vaccinated again before this flu season 11 as immunity (through natural infection or vaccination) declines over time. 12 

Good health habits help stop the spread of influenza 13

  • Avoid close contact with people to reduce the spread of germs
  • Cover your mouth and nose – a person with the flu can spread it to others up to 6 feet away!14
  • Wash your hands frequently and use hand santiser
  • Regularly disinfect surfaces at home, work or school, especially when someone in your household is sick
  • Get some sleep! Lots of fluids, exercise, good food – it’s very important to maintain healthy habits throughout the winter season
  • If you are sick with a cold or the flu STAY HOME. Many companies offer flexible work options so do the right thing by your colleagues and keep away from the office

Check out our tips to keep your kids flu free!

  • For more information please speak to your healthcare professional.


10.  Au\stralian Government, National Notifiable Diseases Surveillance System,