He said the shortage was due to the scientific panel that determines the make-up of the vaccine taking longer to get the formula right, meaning suppliers have also needed more time to manufacture the different vaccines tailored to the individual groups. 

Mr Barrell said there are two types of influenza, A and B, but within those there are also sub strains. 

“There is an international panel that meets twice a year in each hemisphere to review the influenza data from around the world from months previous and tries to make predictions as to which strains would circulate in coming months in each hemisphere.”

As such, there are three flu vaccines in Australia; for people under three years of age, for people between the ages of three and 64 and for people over the age of 65. 

Dr Barrell said the ‘publicity machine’ which recommended people get the vaccine had worked tremendously well this year, exceeding the expectations of government and manufacturers. 

“Whilst we’ve had less than the usual stocks of the over 65 vaccine, we do have a sufficient supply with more to come. We also have a sufficient supply of the vaccine for children under the age of three but the real short fall is with the vaccine for the group of people between the ages of three and 64.”

He said more supply should arrive within the next three to four weeks.