COVID booster shots: What are they and why do we no need them?

Staff prepare shots at government COVID vaccination clinic. Picture: Sitthixay Ditthavong
Staff prepare shots at government COVID vaccination clinic. Picture: Sitthixay Ditthavong

Boosters are on the way.

People aged 18 and over are eligible if it is more than six months since they had the second of the two main jabs.

The date of your second vaccination will be on your vaccination certificate. Your health authority may text you to say that the six months has passed and that you can have the booster.

What is a booster?

It's an extra dose of the vaccine given after the protection from the first two doses starts to wane. The booster helps keep the level of immunity up.

That means it protects you for longer against catching COVID but also against getting seriously ill if you do catch it.

The Department of Health says: "A booster dose will continue to protect you, your loved ones and your community against COVID-19.

"Booster doses will be free for everyone."

Who will get them?

People will get them as the six months since the last jab comes up. Those who got vaccinated first will be eligible for the booster first.

Accordingly, some older people have already had them. They were the first to be vaccinated so their six months mark has arrived.

"Due to the age of residents, and because they were prioritised for early vaccination, many are now due for their booster dose," the Department of Health says.

Because of the time condition, the people at the head of the queue are those who needed particular protection (either for themselves or to prevent infecting vulnerable people). These were primarily health care workers and the residents of aged care homes.

People at greater risk of serious COVID, including people aged 50 and over and Aboriginal and Torres Strait Islander adults, will also be a high priority.

People under the age of 18 aren't on the list because severe COVID-19 is uncommon in that age group, and because the first two doses are thought to give a very strong protection against the virus.

Is it safe?

There is no reason to think that a booster will be any less safe than the original vaccines. There may be mild, temporary side effects but no major risks, just as there were with the first doses.

"Common, mild side effects following a booster dose look similar to the side effects following the first two doses," the Department of Health says.

Those possible side effects are listed as:

  • slight pain after the injection
  • tiredness
  • headache
  • muscle or joint pain
  • fever and chills.

"Most side effects are mild and go away within one to two days," the Department says.

In some very rare cases, parts of the heart can become inflamed (myocarditis and pericarditis).

"Most cases have mild symptoms and recover well," the Department says, but the Therapeutic Goods Administration will monitor the booster's effects.

"Evidence from Israel suggests that myocarditis and pericarditis are not more common after the booster dose, compared with the second dose."


Which vaccine?

The booster will usually be Pfizer of AstraZeneca.

The Pfizer booster should be available whichever vaccine you had first. If you had AZ, the booster could be Pfizer or AZ.

AZ will be available if you can't have the Pfizer vaccine for medical reasons or if you had two doses of AstraZeneca previously.

Are we unprotected after six months?

We remain protected even after six months have passed since the last jab. Protection against severe COVID doesn't suddenly disappear.

According to Steph Davis, deputy chief medical officer at the Department of Health, "two doses is considered fully vaccinated, even if that second dose was a little bit more than six months ago."

But the effects will be studied and policy adapted according to the findings: "It may be that boosters will be recommended for all of us more strongly."

Will it be like the annual flu jab?

It may well be - but the regulators and the authorities will wait to gather evidence from the rollout before deciding.

Scientists will need to study how the virus changes and how long protection from the vaccine lasts.

But one of the hopeful signs is that some of the vaccines are of a new type which are very adaptable to new strains of the virus.

It is likely that boosters will become part of our lives like flu jabs already are.

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This story Why do we now need COVID booster shots? first appeared on The Canberra Times.


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