Top 3 COVID-19 vaccine questions – Booster dose after AZ, booster dose timing and are boosters mandatory

Dr Lucas De Toca, COVID-19 Primary Care Response First Assistant Secretary, answers the top 3 questions across our channels.


Good morning, I'm Dr Lucas De Toca and today we are going to be talking about boosters, hopefully everything you want to know about boosters. As usual, I am joined by Linda, who is doing Auslan interpreting, thank you. I am on land of the Ngunnawal people, so dhawra nhuna, dhawra Ngunawal. Yanggu gulanyin ngalawiri, dhunayi, Ngunawal dhawra. Wanggarralijinyin mariny balan bugarabang. You probably can't tell yet, and I haven’t shaved around it, but I am participating in Movember, so apologies in advance as these segments will deteriorate as my moustache grows over the next few weeks, but it's a really important cause to raise money and awareness for men's health. It started focusing on cancer and other physical conditions and now has moved to a broader scope about men's health in general and particularly mental health. In the context of the pandemic, everyone has been having a tough time and often men struggle to talk about their struggles, isolation, family pressures, financial pressures, job losses. They all have had a significant a toll and also, quite often, we have stopped getting the preventative and routine health care that we need, as we have been focused on COVID and not much else. It's a good time throughout this month to remember that men's health is a really important thing, that is often overlooked. If you are able to donate to Movember because it is a great cause, but in any case, to reach out. If you are suffering and you are not talking about it, please know that there is plenty of help through multiple avenues. If you want to reach out and you have immediate requirements, you can talk to Lifeline, and you can call Lifeline on 13 11 14, you can also go to the Beyond Blue phone line on 1300 224 636. And there is a heap of resources on the website that we put together called Head to Health, so if you go to you will find links to multiple resources and different avenues that suit your needs on how to get help. Let's see how Movember evolves over the next few weeks.

As mentioned, we thought it was important to focus on booster shots after last week, there was a lot of talk around it and the launch of a general booster program for the population, so we are going to be talking about which vaccine to get for your booster shot, the timing interval and spacing between boosters, and whether the boosters are mandatory or not which, spoiler alert, they are not.

Why are we doing a booster program? We know that the vaccines we have available in Australia at the moment, AstraZeneca (or Vaxzevria), Pfizer (or Comirnaty), and Moderna (or Spikevax), are incredibly effective at protecting from severe disease, hospitalisation and death, and also have a significant impact on reducing the risk of getting COVID altogether and transmitting it to others. We also know that two doses of those vaccines protect you for at least six months and that’s really good protection. But we also have some emerging evidence, particularly internationally, on some waning of effect after six months for some of the protection the vaccines provide. There is still a significant amount of protection even after six months and that is why the booster program has been launched as an option for people who received their second dose more than six months ago and they can go and get it. As I said, the fully vaccinated status remains as a two doses or full course of vaccine, but the booster, there is more and more evidence that shows that that third dose after six months significantly triggers a stronger immune response and for longer, so it is currently recommended for anyone who received their full course more than six months ago. At the moment, the TGA, the Therapeutic Goods Administration, has approved the Pfizer vaccine as the vaccine for boosters and that is the advice that the Australian Technical Advisory Group on Immunisation, or ATAGI, has provided. At the moment, if you had your second dose of the vaccine more than six months ago, regardless of which vaccine you got, Pfizer, Moderna or AstraZeneca, you can go to a GP, a state clinic, an Aboriginal health service or, soon, a pharmacy and get your Pfizer booster. There is a strong encouragement for people in high risk groups, people in aged care facilities, healthcare workers, people living in disability care facilities, Aboriginal and Torres Strait Islander people to get the booster, but it is open to everyone in the population as long as you had your second dose more than six months ago. There is very little evidence of the effectiveness of a booster in a shorter interval, so don’t rush to get your booster if your second dose was less than six months ago, even if you are going overseas or you have any other concerns, you can be really confident that your full course is giving you that full protection for at least those first six months. But if it's been more than six months ago and you want to get your booster, make an appointment, go to a walk-in clinic and get your booster shot. AstraZeneca can be used as a booster for people who received the full course of vaccination with AstraZeneca and had no issues associated with it, but the preferred vaccine for the booster program is Pfizer. It is likely we might have more availability of other vaccines for boosters in the future, and there are conversations with Moderna about this and them submitting for a booster shot at some point, but at this stage, regardless of which vaccine you had, Pfizer is the one we are using for the boosters. As mentioned before, the timing is over six months, we really don't recommend it before. Don't worry if you are under that six months interval, you are well protected and after six months you can consider getting a booster. We still don't know, and we have to see how things evolve here and in other countries, whether more than one booster will be necessary. It may be that some population groups, older people, people with weakened immune systems might need more boosters in the future. It may well be that no-one will need more boosters in the future, or it might be that it protects us for a few years as opposed to a few months. That is still unknown but what we know is that really good protection for at least six months from primary course, opportunity to boost it up even further after six months with a third shot and we will see how things evolve. The vaccination program in Australia is not mandatory, getting a vaccine is voluntary, but it’s true that in many jurisdictions and for many professions, there are fully vaccinated requirements to access venues or to maintain occupations, in which if you are not vaccinated you may be putting other people at risk. The definition of fully vaccinated, at this stage, has not changed. Fully vaccinated means you received a primary course, which is two doses of the vaccines, and whether you get a booster or not, that doesn't change your status. It doesn’t change your digital certificate, it doesn’t change your immunisation history statement. We will continue to review the policies as more evidence emerges. A good trick, if you are not sure when you got your second dose, so you are not sure when you are due for your booster or when you are eligible to receive a booster, you can check your immunisation history statement online, or on myGov, or calling the Australian Immunisation Register, or if you have downloaded your digital certificate that many of us carry on our phone, the digital certificate has the date of your second dose, so six months from that date of the second dose is when you become eligible for a booster and you can go and get it if you so choose. That is all we have for today. I'm sure there are many other booster questions that I missed and will be able to address in further segments, but thank you for watching, thank you for staying COVIDSafe, and have a conversation about men's health if you can. Thank you.

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  1. If I’ve had the AstraZeneca COVID-19 vaccine will the Pfizer booster work?
  2. Can I get a booster any time after 6 months of receiving my 2nd dose?
  3. How can I find out if it’s mandatory for me to receive a COVID-19 booster?
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