The Turnstone: talking about vaccines #34
The Turnstone: talking about vaccines #34
The latest on boosters for Covid-19 (5 minute read)
It’s been a while since I wrote about Covid-19, but the virus hasn’t gone away. Far from it. Every day, people are dying. In New Zealand, there are a few people dying each day. In the USA, with a much larger population, it’s hundreds of people each day. In China, the figure is anybody’s guess. The Chinese government is reporting a few hundred deaths per day to the World Health Organisation, although they recently updated their figures. Even then, epidemiologist Michael Baker politely says that the Chinese figure “looks low”. We will have to wait and see what we can learn from figures of excess mortality, which compare the total number of deaths in a particular period with what we might have expected based on that same period in previous years.
Focusing on deaths, however, masks the full impact of Covid-19. Many people survive only after they or their families suffer harrowing ordeals. And then there’s long COVID. A recent article in Nature estimated that 65 million people have been affected.
It is fair to say that Covid-19 remains a dangerous disease and that vaccines remain important. Although these vaccines aren’t providing lasting immunity, there are some new developments with vaccine boosters, so I have put together some resources about these boosters – what they are and what they do.
What are Covid-19 boosters?
If you get a booster shot for Covid-19, what you get depends on where you are.
In some countries, including the USA and Australia, there are now boosters available which target the Omicron variant. These boosters come from Pfizer and Moderna, and use messenger RNA technology. They are known as bivalent boosters because they contain two parts, one part targeting the original virus and one targeting Omicron. It’s a bit more complicated than just targeting Omicron though, because Omicron itself has different forms, known as sub-variants. The first of these bivalent boosters targeted one of the early Omicron sub-variants. A later bivalent booster targeted a later Omicron sub-variant.
There’s a good basic overview of the bivalent boosters on this website:
The Omicron Booster: Your Questions Answered > News > Yale Medicine (6 minute read)
The following article, by Jamie Morton of The New Zealand Herald, also looks at bivalent boosters. Although it’s a few months old now, the information is still useful.
Explained: Pfizer seeks NZ approval for BA.5-targeted vax | RNZ News (4 minute read)
Covid-19 boosters for New Zealand
In New Zealand at the moment, if you get a booster, you’re getting an additional dose of the original vaccine. Mostly, this is the Pfizer vaccine, but Novavax is also an option. The bivalent boosters are not yet available in New Zealand, but they are coming. They’ve been given provisional approval by Medsafe, which is an important step.
Covid-19: Medsafe grants provisional approval for Pfizer Omicron vaccine | Stuff.co.nz (2 minute read)
In the meantime, there is comprehensive information about getting a Covid-19 booster in New Zealand, including who is eligible and where you can get vaccinated, on the website below.
COVID-19 vaccine boosters | Unite against COVID-19 (covid19.govt.nz) (3 minute read)
If you want more in-depth information, there is also a page on Covid-19 boosters on New Zealand’s Immunisation Advisory Centre website. This page contains links to more detailed information.
Booster Doses | The Immunisation Advisory Centre (4 minute read)
It is likely that both of these previous pages will be updated when the bivalent boosters are available in New Zealand.
Covid-19 boosters for Australia
In Australia, both the Pfizer and Moderna bivalent boosters are available. There is general information on Covid-19 boosters in Australia on the website below. If you go to the bottom of the page where it says “Book your Covid-19 appointment”, the link will offer you options for where these boosters are available.
Stay up to date with your COVID-19 vaccines | Australian Government (3 minute read)
Covid-19 boosters for the USA
Both the Pfizer and Moderna bivalent boosters are available in the USA. The following website gives official information on Covid-19 boosters for the USA, including information on where to get the different types of booster.
Vaccines.gov - Find COVID‑19 vaccine locations near you
How well do the new boosters work?
There’s a good, recent overview of the evidence from American doctor and author Eric Topol, on his Substack newsletter, Ground Truths. The short version is that there is now good evidence that bivalent boosters are working. They are doing a better job that the original vaccine in protecting people from becoming seriously ill with Omicron.
The bivalent vaccine booster outperforms - by Eric Topol (substack.com) (8 minute read)
American epidemiologist and writer Katelyn Jetelina, who writes Your Local Epidemiologist on Substack, has also looked at the bivalent boosters. Her article isn’t quite so recent (it was written in December rather than January) but it has some useful information. In particular, she gives more information on protection against infection. The figures she quotes suggest that there’s some increased protection against infection, and it’s better the longer you wait between doses (that is, it’s better to get boosted 8 months after your last dose compared to 2 months after your last dose).
Fall bivalent boosters: Science update round 3 (substack.com) (4 minute read)
And a recommendation…
Despite all the reading and writing I’ve done on the subject, I’m not tired of reading about Covid-19. And now, my favourite science writer, David Quammen, has turned his attention to the pandemic. In his book, Breathless, he speaks with dozens of scientists about their research into Covid-19. I haven’t finished it yet, but it’s an enthralling read if you like to understand the science of infectious diseases. I particularly recommend this book if you want to understand where scientists think Covid-19 came from, and how we know.