8 November 2021

ACT's 95 per cent vaccination rate is only temporary without timely boosters for all

| Karyn Starmer
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Dr Andrew Jeremijenko

Aspen Medical Group Medical Director Dr Andrew Jeremijenko. Photo: Aspen Medical.

While the ACT gives itself a well-deserved collective pat on the back for achieving the milestone of 95 per cent double-dose vaccination for its 12-plus population, medical researchers are warning that without timely booster shots, the population could find itself back to below herd immunity levels and at risk of a third wave.

Research published in The New England Journal of Medicine found Pfizer vaccines offered at least 90 per cent protection against severe COVID-19 cases for at least six months; however, six months after the second Pfizer dose, the vaccine provided less than 20 per cent protection against milder infections of the virus.

The co-author of the research, epidemiologist and Aspen Medical group medical director Andrew Jeremijenko, said that with immunity waning after six months, the effective 95 per cent vaccination rate would start to drop.

“The first groups of essential workers were receiving their second Pfizer dose around April this year so they are due for boosters now. Without boosters, as each individual reaches the six-month mark, they will effectively move out of the 90 per cent protected group and the overall population vaccination rate will progressively slide down to below herd immunity levels,” Dr Jeremijenko said.

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Dr Jeremijenko said the vaccines will remain effective against severe infection, resulting in hospitalisation and death, for longer than six months, but noted with waning effectiveness, the chance of acquiring the virus and passing it on will increase.

A study undertaken by University of Oxford scientists published in August found that the effectiveness of the Pfizer vaccine declines slightly faster than that of AstraZeneca.

Without booster shots, Dr Jeremijenko suggested Australia may end up with a similar experience to Israel which had a spike in cases six months after its vaccination program started, creating a third wave.

Like Israel, Australia has experienced very low infection levels from the SARS-CoV-2 virus compared with other countries. Dr Jeremijenko says this means boosters are crucial to maintaining herd immunity.

“Places where infection rates were low will be especially reliant on booster shots to prevent further waves,” Dr Jeremijenko said.

This is different for countries like Qatar where SARS-CoV-2 infection rates were higher.

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A Qatar study co-authored by Dr Jeremijenko showed that prior infection was associated with a lower risk for breakthrough infection among persons receiving the mRNA vaccines like Pfizer and Moderna, meaning natural immunity from infection together with vaccination together lasts longer than vaccinated immunity.

Several recent studies showed Moderna’s shot elicits a stronger and longer-lasting immune response than the Pfizer jab. Some scientists believe this is because Moderna’s mRNA dose is more than triple that of Pfizer.

While studies are continuing, Dr Jeremijenko says it was clear that while vaccine efficacy waned over time, every country would probably need to follow Israel’s lead in administering boosters to its entire population with older adults and those in a clinical risk group prioritised for booster doses.

The ACT Government has opened bookings for its booster shot program. People who received the vaccine at least six months ago are now eligible for their top-up.

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My husband and I are both double vaxxed and we both contracted covid. My husband has recovered fairly well but I am still struggling with my recovery. I have very weak muscles and am still very tired all the time. It affects all people differently.

How about I just get a transfusion of Pfizer. Will that do?

Everyone who HAS had both shots already – does need to wait 6 months from their second shot. In our case that means we wait until February. And we were in what was called the 1b grouping. which puts us among the earliest to receive both shots!

In that case, where’s the URGENCY?!

So, I’d respect your posts a whole LOT more, if that factor was incorporated in all future posts by you, Karyn!

That it hasn’t been mentioned up to now, rather diminishes your accuracy and probity!

We WILL have our booster shots – in February. When they will work!!

I’d suggest the urgency is for the 1a frontline workers who were vaccinated in March/April. High risk due to occupation and in need of third jab to manage waning immunity. Don’t want them waiting until after Christmas, or “later” when it is convenient.

The ACT has not achieved herd immunity for Covid. Nowhere in the world has achieved herd immunity.

It’s fine to promote the benefits of vaccination amd booster shots, but at least be honest about why.

Too right, Chewy and see above for another factor.

My Pfizer shares !

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