Expert Reaction
These comments have been collated by the Science Media Centre to provide a variety of expert perspectives on this issue. Feel free to use these quotes in your stories. Views expressed are the personal opinions of the experts named. They do not represent the views of the SMC or any other organisation unless specifically stated.
ATAGI’s updated advice and expanded recommendations surrounding a winter dose of the COVID-19 vaccine signals a more nuanced approach in managing COVID-19.
By suggesting individuals over the age of 30 evaluate their personal situation, it identifies and recognises that any decision to receive further doses of COVID-19 vaccine relies on both population factors but also an individual’s benefit-risk ratio. Whilst age and medical comorbidities are important risk factors for severe COVID-19 infection, other factors such as vocational exposure to COVID-19, history of COVID-19 infection, recency of previous COVID-19 vaccinations or even factors like imminent travel to areas where COVID-19 is prevalent may tip the balance in favour of someone over 30 years old obtaining the winter dose sooner rather than later.
This approach also highlights the impact that a high rate of vaccination and immunity across the population can have in helping to reduce the burden that COVID-19 places on our health system and workforce, which continues to heave under the regular winter strain of influenza and other respiratory illnesses.
Any decision to receive the COVID-19 vaccine has to balance benefits of boosting immunity against the waning effectiveness of the current vaccine against newer Omicron sub-variants as well as any the small risk of safety and adverse events from vaccination.
As immunity post-vaccination wanes after 3-4 months a 4th dose is important during this third wave of the BA4 and BA5 variants to reduce hospitalisation and severe disease. COVID and influenza co-infection is associated with more severe disease so a COVID and influenza vaccine dose is ideal to protect yourself during winter. Severity of disease increases with age, so those over 50 years are especially encouraged to receive a 4th dose of COVID vaccine.
For adults < 30 years of age the risk of rare adverse effects such as myocarditis in higher, especially for young males and COVID disease less severe, so the risk benefit of a 4th dose is different compared to ages group where severity of disease and hospitalisation is higher. Availability of omicron variant vaccines will likely improve protection against these variants.
In my view, increasing the availability for a fourth dose is a very good decision. It is clear that vaccination protects against severe disease from SARS-CoV-2. However, with the Omiron variant, this protection wanes after 3-6 months. Currently, Australia is experiencing the largest COVID-19 wave to date, mainly due to the infectivity of the Omicron variant, and the fact that very few people have been infected in the first waves. Thus, even though hospitalisation rates are much lower in vaccinated individuals, the high infection rates lead to high numbers of patients requiring extra care. Thus, again, the hospitals are put under enormous pressure. Any measure to alleviate this is very welcomed. We do know that vaccine-induced antibodies are less efficient in binding the Omicron variant. However, it is clear from scientific data that booster vaccinations do improve both the total antibody levels and the capacity of these antibodies to bind Omicron. This will undoubtedly ensure that after a booster dose, your risk of severe disease is strongly reduced, thus protecting yourself, and people around you, either directly, or indirectly by alleviating pressure on the healthcare system.
Jaya Dantas is Professor of International Health in the School of Population Health at Curtin University
The vaccine mandate has been controversial, and in most countries, has been discontinued. A significant number of Australians have already had COVID, are triple vaxxed and have had their flu shot, so are prepared to face the remainder of winter.
Health workers, aged care workers, other workers in people facing professions (teachers and prison workers), and those with chronic conditions and immunocompromised people should consider the additional booster for extra protection.
The Australian Technical Advisory Group on Immunisation (ATAGI) has now recommended those ages 50-64 to receive a fourth COVID booster, in addition to the recommendations already in place for 65+ and Aboriginal and Torres Straight Islanders 50+. Additionally, the winter booster is also available to 30-49 year olds.
“This is in response to an impending third Omicron wave being generated by two new viral subvariants (known as BA.4 and BA.5). These variants are fast becoming the dominant strains in Australia, and have been shown to be able to challenge our immunity to COVID-19.
“The aim of receiving the fourth shot is to increase our immunity to peak levels as the virus surges around Australia in winter, to help reduce hospitalisations and severe illness from the virus.
As I am writing this, I am successfully booked in for my 4th dose of a COVID vaccine booster as one of the over 50s! It will also be good news for other age groups 30s and up to also be allowed the option of an extra booster this winter, especially as flu is prevalent.
The current COVID landscape has been painted with new arrivals of BA.4 and BA.5 subvariants of Omicron. These clever variants have learned to evade our immune responses and even ignore vaccine induced antibodies. So booster shots will help lift our levels of protection so we can manage disease, reduce hospitalisations and hopefully prevent more deaths.
However, people aged 20-29 have had the highest caseloads, and since they are highly mobile they tend to shed virus everywhere. Travel has opened up with unrestricted borders and people are starting to jet-set around the globe. Most of us who had 3rd doses back in January are finding that our anti-viral antibodies have waned over the 6 months, potentially becoming vulnerable to reinfection.
An optional winter booster would be warmly welcomed by all.
Paul Griffin is Director of Infectious Diseases at Mater Health Services, Professor of Medicine at the University of Queensland, and Medical Director and Principal Investigator at Q-Pharm, Nucleus Network
In my opinion the expanded eligibility for the fourth dose is welcome news as even a modest amount of additional protection is going to be of benefit as we experience a significant wave of transmission of the more infectious subvariants of BA.4 and BA.5. This is not however a complete solution in itself.
We need to focus primarily on getting those people already eligible for additional doses up to date with their vaccinations. We also need to do more to ensure people who are eligible for therapies get access to them in a timely manner. We also need to reinforce the basic measures that helped so much early on in the pandemic including mask wearing, social distancing and a basic awareness of other risks including ensuring adequate ventilation.
One common question is should we wait for the Omicron specific boosters and while these are looking very promising and likely to be available at some point this year, given the situation at the moment, it is important for as many people to get vaccinated now as possible. Perhaps we just need to ensure people are aware that even a fourth dose now, while of benefit and recommended, is not likely to be the last dose required, and may not even be the last dose recommended this year.
Once again, the requirement for an update in our vaccination strategy is not an indication that our strategy thus far has been flawed or that our vaccines have not worked tremendously well, but further evidence of just how hard this virus is to combat and how quickly the situation changes as a result.