On Thursday, based on expert advice received from the Australian Technical Advisory Group on Immunisation, the Commonwealth Government moved to adjust Australia’s vaccination program.
The medical advice to the Government is that the risk of blood clotting side effects from the Astra Zeneca vaccine is four to six in one million people, in the first four to 20 days post the vaccine.
This is a rare but serious side effect. One case has been reported in Australia to date from about 420,000 Astra Zeneca doses. It is also possible that the risk of this blood clotting is lower with increasing age.
On that basis, the recommendation is that it is preferred that the Pfizer vaccine be provided to adults under the age of 50. The Astra Zeneca vaccine should only be given to adults under the age of 50 where the benefit clearly outweighs the risk for that individual. Astra Zeneca continues to be recommended for adults over the age of 50 given the ongoing risk of COVID-19 in Australia.
This decision is all about balancing risk with benefit. Although we don’t currently have COVID-19 in our communities, the risk of an incursion of the virus is ever present.
The risk of severe disease from COVID-19 is strongly linked to age. The death rate from the virus for a 50-year-old is estimated at 1.3 percent. For perspective, this means 13,000 in one million 50-year-olds will likely die from the virus, compared with for four to six people in one million who will suffer blood clotting which may not result in death.
The benefit of being vaccinated is therefore much higher for older people. It is the view of our nation’s medical experts that this benefit outweighs the risk of blood clotting in older people.
Australia is in a unique position to approach this risk with an abundance of caution. In countries where death rates are high, including the United Kingdom, the risk of not proceeding with the Astra Zeneca vaccine is much greater than the risk of side effects.
As with all medical treatments, individuals need to consider the risks and benefits. The Government respects a person’s choice to make an informed decision on whether to accept the risk associated with vaccination and encourages Australians to seek out the advice of their doctor.