Will Australia follow Europe into a fourth COVID wave? Boosters, vaccinating kids, ventilation and masks may help us avoid it
- Written by C Raina MacIntyre, Professor of Global Biosecurity, NHMRC Principal Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW
Europe is facing a fourth wave of COVID[1]. As we watch on, it is reasonable to ask whether Australia will be confronted with the same fate.
Several factors will determine this: vaccination rates, high uptake of third dose boosters, vaccination of children and whether a comprehensive strategy of ventilation with vaccine-plus[2] measures including masks, testing and tracing are used.
New OzSAGE[3] modelling for NSW shows possible[4] increasing cases from mid-December with a predicted peak in February 2022, despite high vaccination rates. OzSAGE warns if contact tracing is not maintained and children 5–11 remain unvaccinated, hospitals may be overwhelmed again. But if we vaccinate young kids and maintain high testing and tracing, the outlook is good.
If not for Delta …
If the ancestral strains of the virus that dominated infections in 2020 were still in pole position, we would now have COVID well controlled[5] in countries that achieved higher than 70% of the whole population vaccinated.
Unfortunately, just as the vaccines became available, new variants of concern began emerging. The currently dominant Delta variant raises the stakes because it is far more contagious and has some potential to escape the protection[6] offered by vaccines. This means we need very high rates of vaccination across whole populations – probably over 90% of everyone vaccinated including younger children – to control the virus.
In addition, we need to start thinking about “fully vaccinated” being triple, not double, vaccinated.
Germany has entered into a ‘nationwide state of emergency’ because of surging COVID infections.
Matthias Balk/dpa via AP[11]
France, too, has been slow and restrictive in making boosters available for adults, with people over 50 eligible[12] from this December. Likewise, Ireland only approved boosters[13] for people 60 years and over at the end of October.
The evidence is clear that boosters are needed[14]. So, on the background of inadequate vaccination rates[15] ranging from 64% in Austria to 76% in Denmark, a slow and restrictive approach to boosters, together with abandoning other measures such as masks, has left many European countries vulnerable.
Read more:
Australians will soon receive COVID booster vaccines. Why do we need them, and how effective are they?[16]
Austria, with one of the lowest vaccination rates, has one of the highest rates of COVID, prompting it to be the first European country to mandate vaccines[17].
Much of the fourth wave is also being driven by transmission in children. The EU has been slow to approve vaccines for younger children, prompting Austria to commence vaccinating children without EU approval[18].
World in Data, CC BY[19][20]
Too much reliance on vaccines?
The fourth wave follows the relaxation of COVID restrictions like masks, density limits, testing and tracing; and failure to address safe indoor air[21].
The Delta virus is a tenacious beast, and the vaccine alone is not enough[22] to tame it. Country after country has shown this, including Denmark, which ceased all restrictions, including masks in September and is now facing a large surge in cases[23] despite relatively high vaccination rates.
The prospect of a fourth wave also depends on the epidemiology of SARS-CoV-2. There is a high probability new variants will emerge that will challenge us further, either because they are even more contagious or more vaccine-resistant.
That said, we have seen spectacular advances in science, with vaccines produced in less than a year. There are many more second generation vaccines and matched boosters in the pipeline, and promising new antivirals[24] for early treatment. So our ability to fight this virus will keep improving.
Read more:
Pfizer's pill is the latest COVID treatment to show promise. Here are some more[25]
What about Australia then?
So will Australia also face a fourth wave? Yes, it’s likely because SARS-CoV-2 is an epidemic infection. It will continue to cause the waxing and waning cycles of true epidemic infections just like smallpox did for thousands of years, and like measles still does. However, it’s possible we can achieve elimination of COVID[26] just as we have with measles, and only see small outbreaks.
Author provided
If we’re successful, outbreaks may still occur – but they will not become sustained or uncontrollable. Here’s what Australia can learn from Europe and other countries:
firstly, we need to aim for at least 90% of the whole population vaccinated – this should be done equitably for all states and territories, for remote and regional areas and for all subgroups including children
we need to be agile and responsive to evidence, including the need for subsequent boosters. If a new vaccine or Delta-matched booster comes along that improves protection, we need to add that to the tool box rapidly
childcare and schools are fast becoming the new frontier of COVID[27]. We must ensure safe indoor air, masks and vaccination for younger children[28] by the time students return from summer holidays in 2022
vaccines alone are not enough, so let’s not be like Denmark and embark on magical thinking. We need to address safe indoor air[29] and have a vaccine-plus strategy. That means masks in indoor settings, maintaining high testing and tracing levels, protecting younger kids until they are eligible for vaccination and ensuring high uptake of boosters.
If we acknowledge the airborne transmission of COVID and adopt effective ways of preventing[30] this virus, we can defeat it.
But that requires a layered, comprehensive strategy of ventilation, vaccine-plus measures and the ability to move quickly with evidence as it becomes available.
New vaccines and new ways of employing them are hopefully on their way. Until they eventuate, we’ll need to be ambitious in our COVID strategy and keep using ventilation, masks and other measures to avoid a severe fourth wave.
References^ a fourth wave of COVID (www.news.com.au)^ vaccine-plus (ozsage.org)^ OzSAGE (ozsage.org)^ shows possible (ozsage.org)^ we would now have COVID well controlled (www.sciencedirect.com)^ escape the protection (www.nature.com)^ World in Data (ourworldindata.org)^ CC BY (creativecommons.org)^ No, vaccinated people are not 'just as infectious' as unvaccinated people if they get COVID (theconversation.com)^ changed the recommendation (www.dw.com)^ Matthias Balk/dpa via AP (photos-cdn.aap.com.au)^ eligible (edition.cnn.com)^ approved boosters (www.euractiv.com)^ boosters are needed (theconversation.com)^ inadequate vaccination rates (ourworldindata.org)^ Australians will soon receive COVID booster vaccines. Why do we need them, and how effective are they? (theconversation.com)^ mandate vaccines (www.theguardian.com)^ without EU approval (www.nytimes.com)^ World in Data (ourworldindata.org)^ CC BY (creativecommons.org)^ safe indoor air (ozsage.org)^ vaccine alone is not enough (theconversation.com)^ now facing a large surge in cases (edition.cnn.com)^ promising new antivirals (www.cnbc.com)^ Pfizer's pill is the latest COVID treatment to show promise. Here are some more (theconversation.com)^ we can achieve elimination of COVID (www.thelancet.com)^ new frontier of COVID (www.smh.com.au)^ safe indoor air, masks and vaccination for younger children (ozsage.org)^ safe indoor air (youtu.be)^ adopt effective ways of preventing (theconversation.com)
