Because the failed immunity rate for the AstraZeneca vaccine is more than seven times that of the Pfizer vaccine, if the Australian rollout takes place as planned, about 5.5 million people (22% of the population) could still be at risk of getting ill, while some of the remaining 20 million could still become infectious but be asymptomatic.
Covid vaccines and the unknown unknowns
What we know about Covid-19 is that there is much we don’t know – about the virus itself and the vaccines on offer. All this uncertainty is driving the state and federal governments to be very cautious.
We can expect Australia to continue with international border controls and quarantining of all arrivals in some form. We note the discussion about building facilities around the country and suggested refinements of the CBD hotel systems. Other countries, despite vaccination programs, are using similar or other methods to control entry.
Regrettably, uncertainty might also be driving the federal government’s rush to vaccinate (most of) the whole population, no matter what.
Even with all the vaccines available, a certain proportion of the population will not be immune from Covid despite being vaccinated. Hence, problems will continue until we use high efficacy vaccines and the world gets to the ‘herd immunity’ stage, where the virus dies out and has been eliminated, if not eradicated.
Here we mention the main areas of uncertainty.
Mutations: The virus is changing and some mutations might be even more infectious and more deadly and the current vaccines might not be effective against them. Will we have to vaccinate everyone again because of a significant mutation?
Long term effects of vaccines: The current vaccines have been developed at record pace and are not fully tested in the community in regard to longer-term negative effects.
Efficacy v effectiveness: Efficacy is the ‘success’ rate in the trial stage, with testing on a restricted range of subjects. Effectiveness is the ‘success’ rate when the vaccine is finally administered to the population, that is to the real world. These rates might differ. We might eventually find that a vaccine with a high published efficacy rate is significantly less effective in the real world and/or for some groups, such as the elderly.
Differing efficacy rates: The Pfizer vaccine has a published efficacy rate of 95%; the AstraZeneca vaccine has an efficacy rate quoted as low as 62%. Thus with Pfizer we would expect that of those who would normally have become ill without vaccination, there would be 95% fewer; with AstraZeneca we would perhaps expect only 62% fewer.
Differing protection rates: Of those who have Pfizer, it seems only 5% will not have immunity; with AstraZeneca perhaps up to 38% will not have immunity. The failed immunity rate for AstraZeneca is more than seven times the failed immunity rate of Pfizer.
Symptomatic v infected: This article provides some explanation of what the Covid vaccination testing involves. What the Pfizer vaccine measured was the number of people who became ill (symptomatic) after having had the vaccine, but not the number of people who became infected after having the vaccine. Thus, it seems that swab testing was not incorporated, which means that while those in the 5% were clearly infected, some in the 95% group might in fact still have caught the virus, not shown any symptoms and still have been infectious to others.
The vaccinated can still become infectious: We saw above that it seems the Pfizer is much better at reducing illness in the community. However, a vaccine with a high efficacy score might still produce many asymptomatic but infectious individuals who go undetected and who could potentially spread the disease. Thus a ‘vaccination certificate’ does not mean that someone is not infectious.
Severity of symptoms: The efficacy rate might not be a useful indicator of how ill those who are vaccinated but still get the disease could become, though there is hope that the vaccines will significantly reduce the severity of symptoms and the need for hospitalisation.
How long they are effective for: Will the vaccines be effective forever? For some years with boosters needed? For only six months? Will yearly injections be required, like the flu?
Multiple infections: Can people who have had Covid catch it again and become infectious, and possibly be asymptomatic?
Long-Covid: Many who have acquired the disease, from mild to severe cases, have reported long-term debilitating effects. Will the vaccines be effective in stopping long-Covid?
Existing cases: Are the vaccines of any use to those who have the disease now or who acquire it before being vaccinated?
Conflicting opinions: Disagreement amongst health experts, scientists and politicians add to uncertainty and concerns.
Australia might not reach herd immunity with our current strategy
Herd immunity relates to a situation where the degree of immunity (from past infections combined with vaccinations) is so high that the disease will not pass on or take off in any significant way. With herd immunity, there is still the risk that an infectious person could enter the community and infect some of those not immune, but the spread will not go far and will be short lived in terms of number of cases.
Australia’s current situation is the complete opposite of herd immunity. Yes, under current pre-vaccination policies the chance of anyone catching Covid is effectively zero and any outbreak does not go far or last long. However, open our international borders, stop quarantining and contact tracing and we might soon look like Bolivia, with “bodies piling up at homes and on the streets”.
This article explains why Australia won’t reach herd immunity with the current plan and why information about our two key vaccines “should prompt an urgent rethink of our vaccination strategy”. In short, the AstraZeneca vaccine with its 62% efficacy is inadequate to offer herd immunity.
The pointers appear to be against using any AstraZeneca, and that the strategy should be changed to using the Pfizer on the high risk groups, protecting the rest of the community via quarantining and delaying the rollout for the rest of the population until we have enough Pfizer doses or until we have access to one with a comparable efficacy rate (such as the Novavax vaccine).
(There is some discussion about the AstraZeneca efficacy rate. It is up to decision makers as to what level they choose to work with; to be conservative we have used a lower figure here.)
Once the rollout is completed as planned, those who have been given the AstraZeneca vaccine, based on the efficacy figures, will be running a greater risk of catching the disease than those with the Pfizer vaccine, and will still need to be protected.
Thus, assume the 20 million Pfizer doses are given to the 10 million most deserving and vulnerable Australians. Everything else being equal, they will have a risk factor of 5% of developing the disease compared to not being vaccinated. Assume the other 15.5 million Australians are given the AstraZeneca vaccine. Their equivalent risk factor could be as high as 38% (if the efficacy rate is as low as 62%).
That combination of two vaccines will be an improvement on having no vaccine, but not sufficient improvement. On the basis of the efficacy rates, it seems we can estimate that 500,000 of the 10 million who had the Pfizer vaccine would not have immunity and still be at some risk of catching the disease and becoming ill; and that more than 5 million of those with the AstraZeneca would not have immunity and, likewise, would still be at some risk.
We can thus conclude that if the Australian rollout takes place as planned, about 5.5 million or 22% could still be at risk of getting ill from the coronavirus, while some of the remaining 20 million could still become infectious but be asymptomatic. The raw risk factor is not altered for those not vaccinated so these numbers will be somewhat higher given that a (large) number will not have a vaccine.
These rates would seem too high for us to open our borders to the rest of the world. Hence the need to question the use of the AstraZeneca vaccine. If fully vaccinated by Pfizer, the estimated number of those who would not have immunity and be at risk would be closer to 1.2 million.
The government and health officials might decide that herd immunity is not necessary and that, like the flu, we will live with the virus, hoping outbreaks are not widespread or catastrophic. Without worldwide immunity, however, there is the risk of dangerous mutants appearing.
In Part 3 we explain why a ‘vaccination certificate’ is no guarantee of a person’s infectious status but unfortunately could still become a method of discrimination. And we look at the vaccine take-up rate in light of concerns about the effectiveness of AstraZeneca.
Robin Boyle lectured in statistics at Deakin University and preceding institutes for three decades until 2009. His academic background in mathematics, economics and finance, as well as statistics, led him to developing teaching software in those areas and to be widely sought after as a textbook author.
Comments
24 responses to “Herd immunity? Not with AstraZeneca in the frame. Part 2”
As I read Robin’s evidence the lowest risk option for Australia now is to put the vaccination programme on hold.
Mr Roberts: I like these thought provoking posts.
Yet irrespective of a health need, there is likely a political need to vaccinate – especially in several States. See my comment on yesterday’s post.
Recently over 5 million people in two States were subject to several days home detention, ordered by officials, ‘for’ a single within-community transmission (to a person’s partner).
Several State borders were closed, and then re-opened well before the time those States and experts had repeatedly put to the High Court would be safe after an ‘interstate outbreak’.
Unsurprisingly, despite pleas of Premiers, there were reported toilet paper panics.
As was the case earlier in the pandemic, the panic-reaction, started in Qld, proved contagious.
Given the erratic and at times dishonest performance by Premiers, who would believe this wont happen again. In a snap.
That position is not remotely sustainable in either economic or social (rule-of-law) terms.
It may be the ‘objective’ anti-Covid need for such actions arises from hidden public health resourcing inadequacies and very apparent severely defective governance. If so, the situation may not be sustainable in public health terms either.
Vaccination may provide a face saving circuit breaker, given the dearth of resignations and sackings.
It may allow Australia to crawl out of the strategic hole dug by State over-action and Commonwealth inaction.
Best wishes
When a person dies within minutes of receiving vaccination the word gets out. See a current post by C.J. Hopkins. American journalist Mike Whitney is outspoken on the issue. On the points you raise my copy of a book by former Victorian Treasury economist Sanjeev Sabhlok is on the way. The title is “The Great Hysteria and the Broken State.”Opinion appears to divide two ways, perhaps influenced by personality types. Some see the virus as a public health issue. Others, like me, are more concerned about the ease with which we are drawn into a police State.
Always enjoyed C.J. when he was at Counterpunch, Jerry, just wondered where he went.
And, had much correspondence with Mike Whitney when he was at Counterpunch. Still got the emails somewhere. Must dig them out, and remind myself of how Mike came around to the idea that V. V. Putin would eventually ‘design’ the multipolar world.
Munich Security Conference, 2007 – the beginnings of the geopolitical reframing., and driven since by 3 of the most significant global players in half a century; V.V.P., the greatest FM since Chou En Lai, Sergey Lavrov, and more recently V.V.P.’s now geopolitical ‘bestie’, the Xi -Man.
Most ‘white-men’ hate the notion. Stuff ’em or, at a minimum, never, ever underestimate the ‘enemy’.
I recall seeing the Anglo Chinese scholar, Martin Jacques, talking at Melb Uni, 8 odd years ago. When asked to describe why he thought so highly of the Chinese leadership, he said; ‘They’re just brilliantly competent’.
We should be half as lucky.
I watched the Oliver Stone interviews with Putin and asked myself if I could think of any political people in the West who could demonstrate such a grasp of what is going on in the world. Blowed if I could. I love watching Lavrov and I think I saw the Martin Jacques speech on YouTube. Old-timers from the Canberra Press Gallery recalled how they pestered Curtin for a briefing on the state of play while he was walking around the corridors of the old Parliament House one night. He ushered them into a room where there was a map of the world and gave them an impromptu, masterly lecture on the world at war. No advisers, no briefing notes, just a great brain. Where did we lose it? I think the managerial approach looking at everything in terms of short-term market advantage has had a lot to do with our decline.
Yes, the Ollie Stone interviews were fascinating. Stone talking about the interviews also suggested he found Putin fascinating, very much along the same lines as you – his “grasp”.
Interesting mention of Curtin and the Press Gallery – cheers, liked it. Impossible to see either Morrison or the current Press Gallery even being interested in such a discussion, leave alone any possibility of making meaningful contributions, or departing better informed.
Just one minor quibble, Jerry – not just “short-term market advantage”, ‘short-term everyfreakingthing’
A tad harsh on the Premiers, Petal.
Beezelbub Morrison doesn’t attend the ‘School of the Herd Immunity Dribblers’, like Boris the Falafel, and Scandinavia’s finest recidivist fascism fanciers, the Sveeeeedes, and play ‘wave on through’ to multi storey petri dish tourist ships, the whole show’s a cakewalk, given this is an island.
But, no, Beezelbub just loves to ‘stay open’, for everything other than pandemics of sexual assault on board his own multi storey petri dish shit of state.
DJT: may be relative. I thought they were treated leniently:
e.g. officials in all States bar NSW have made lockdown and border closure decisions. According to their legislation, without assistance from politicians. Which needs to be believed – otherwise the decisions could be illegal and the assisting politicians potentially corrupt – see Loeilo v. Giles Vic Supreme Ct.
And the first duty of the Commonwealth Government is to uphold the Constitution. Which Morrison et al have not only ignored re Covid, but far far worse ignored re the new emergency legislation. Epic fail I think is the term. And the opposition? They deserve a small o at best. Make that zero.
Maybe I am too stupid to see it, but my basic question about vaccines – do they prevent spread (and how) – is yet to be answered. If ‘no’ the policy should be: everyone should get vaccinated, for their own sake. Then the expert mumbo jumbo can start.
On which RACGP website carries an interesting discussion on efficacy (mid mumbo jumbo posing the basic question again).
I’m with this Dr: ‘It’s not helpful for these experts to come out in public to slam the Oxford vaccine. There are many vaccine hesitant people already and we want to increase uptake and have as high compliance as possible. There are many other considerations in vaccine choice that have determined Australian decision; storage, cold chain, availability, price. If these experts have issues then they need to raise them with the advisory group directly rather than via media.’
Please dont take that as a criticism of Pearls or Mr Boyle – who have done exactly the right thing and raised their concerns in a reasonable, reasoning, forum no doubt read by the advisory group. Pearls is anti-media!
Best wishes
To use one of your own, Petal, I think a number of those who have questioned the Oxford/AZ vaccine have done so in “relative” terms.
And, you’re right, there is no scientifically accepted view on the efficacy of any of the vaccines preventing spread. Advantages have generally been couched in terms of the effectiveness in preventing ‘severe disease’. While such prevention would likely help suppress spread (e.g. by keeping people out of hospital), it’s hardly a linear correlation to the prevention of spread, and the aim of eradication.
So, methinks we’re likely stuck with the bug, and will have to rely on preventing/limiting severe disease, and a suite of treatments should the disease get away beyond the upper respiratory tract.
One big advantage of such a combo might be to prevent ‘long-COVID’ in lots of people. Reading recently of cytokines (left over from ‘storms’) being found to have travelled from spinal fluid, to the brain, thus exacerbating the long COVID symptoms, was just a tad concerning, particularly in one case study of a very fit 30-something. He’d suffered a mild COVID, yet was worse off 5 -6 months later, and pretty much unable to function at anywhere near his previous capabilities, or get past the ‘brain fog’ to think about a way forward.
DJT: Thanks.
A reason I like Pearls is because of comments like yours.
You would know a lot more about medicals than me, and your point about the non-lethal effects of Covid has been largely ignored except by Prof Dwyer in Pearls!
My point is not medical.
It is that a circuit breaker is needed to stop officials in most States – some below Dept Head level – from perpetuating the apparent myopic monomanic madness we have seen (worsening) since March last year.
Removal of their Covid directions powers – instead Parlt placing them with a single Minister and consolidating those powers with other responsibilities – would be best.
Despite Victoria being virtually told to do so by its Supreme Ct (in Nov 2020), it created another bureaucratic silo, due to recomms of the hotels inquiry (which seemed unaware of the Supreme Ct ‘next-door’ views).
Widespread vaccination provides a softer excuse to drop the State-of-origin idiocy – whether it ‘works or not’. As Premiers and some officials – who wouldnt know whether ‘it works’ are saying.
The breathing space – not from Covid but their cfit – might be used to get governance closer what is acceptable post the English revolution.
To deal with the likelihood Covid is here to stay.
Thanks again!
There is one overwhelming consideration which is lesser considered by all who ‘protest’ restriction for whatever reason;
‘What if I catch the bug, and infect a dear one, and they succumb to the bug, while I’m beefing about me freedumbs?’
I live alone, and have suffered no detrimental effects, mentally or physically, by being ‘isolated’ due to the bug.
Dya know John Martinkus? Journo, John, very involved for a long time in the region. Advocate for the Timorese, and the West Papuans.
To quote him recently;
“You know the East Timorese experienced 24 years under curfew from the Indonesians. Every night around six pm there was a great rush to get home before you would be shot by the Indonesians. I caught the last few years. A bit of perspective here Victorians.”
Reality bites, Petal.
In medical language, DJT, you are saying the pandemic is now endemic. Science has kicked the own goal of the century by persisting with obscenely dangerous gain-of-function research even after this practice was banned in USA. Covid-19 appears to have come out of a laboratory but good health does not come from laboratories. It is about the way we live.
Not convinced it came out of a lab, Jerry – still lots of evidence to be trawled through, such as that gathered by a group of Italian medicos. They went back and got the tissue samples that had been retained from a cancer screening study, in late ’19, somewhere up around Lombardy – which was hit very hard by the Covid bug, in early ’20. They found plenty of evidence in those tissue samples that a number of those screened have been infected as early as Sept ’19.
Now, until someone provides an explanation suggesting those Italian medicos have stuffed up or fabricated those results, I’ll just leave it sitting on the timeline, with a question mark.
Endemic? Viruses, biological infections generally, yeah, reckon so.
As you say, it’s about the way we live, incl ‘developing’ by pushing further and further into the habitats where various ‘biologicals’ not well tolerated by humans have existed for many a long day.
I’m also not entirely convinced the US banned ALL gain of function research, including the ‘outsourcing’ thereof.
Precisely — outsourcing. Unreasonable to blame the Chinese. Bret Weinstein is interesting on that point about the scientific community generally. One of his points is that mutations growing more dangerous rather than less points to laboratory enhancement. Over my head, of course. Had not heard of the Italians. The other theory is outer space from Australian scientist Ted Steele, who has form starting with an unpopular hypothesis and finally winning acceptance. The September date is interesting. I thought October was the earliest. I have heard the Russian Sputnik vaccine described as the safest because it is “the least ambitious.” We don’t have that option in Australia, as far as I am aware.
On the scientific outsourcing, I saw a slightly clipped version of a doco on Vladvision last week.
The doco is called “Eminent Monsters’. Interestingly, it was a co-production b/w BBC Scotland, Hopscotch, and a few other Western prod’n companies.
I say interesting because Eminent Monster No 1 was a Scotsman, and son of a Presbyterian Minister.
Ewan Cameron, Donald Ewan Cameron or D. Ewan Cameron – psychiatrist, went to US and made a ‘real’ name for himself.
The doco was made recently, given Trump features.
From ‘experimentation’ in a Canadian mental facility in the ’50’s, to a ‘CIA Torture Manual’ soon after (try “KUBARK”), to the ‘Hooded Men’ in Ireland, around ’71, to the European Court in the ’80’s (IIRC), who ‘judged’ the Hooded Men to have been treated rather poorly, just not ‘tortured’, to 9/11 and the 2 Yank psych’s who were paid $180M to ‘specify’ the black site/rendition program, incl Guantanamo, to the rationalisation of the whole show as ‘Enhanced Interrogation’, with CIA and other Yank legal minds taking the European Court decision as ‘precedent’, and here we are, with Assange sitting in Belmarsh, Snowden in Moscow, Europeans (Spaniards) locking up rappers and Catalan pollies for ‘speech’, and the Brits pouring millions of quid into the ‘Institute of Statecraft’ and ‘Integrity Initiative’, in efforts to convince enough Russians that Navalny’s a great guy, and best they get on and regime change Vladimir outta the way.
An alt- title for the doco; ‘The Mother of All Psyops’.
The full version of the doco, which I have since watched, is available on the tube facility, and a few other spots. I was familiar with most of the parts, but the doco does a fair job at putting together the sum of those parts.
Not sure if I’m feeling strong enough for this medicine, DJT. Many of the psychologists would have known that the most successful German interrogator of World War Two was an aristocrat who treated RAF pilots like gentlemen (which they were), offered them coffee and American cigarettes and chatted pleasantly. People like to talk, even when they are trained to say nothing.
Harden up, Jerry!!
Oh, and given you mentioned interrogation techniques in WWII, you may (or may not!) enjoy Jeffrey St.Clair’s Part 1 of; “How Real Nazis Came to the Americas: the Recruitment of Klaus Barbie”, at Counterpunch.org last Friday.
A real stomach churner, including the ‘role’ played by the Croatian ‘man of the cloth’, Father Krunoslav Draganovic.
To be relative, the Hooded Men got off ‘light’.
No, we don’t have the Sputnik option, Jerry. But, the Czechs might soon have. They’ve written to Vladimir, and said they’d like some – and bugger the EU Medicines Authority approval.
They seem quietly confident Vladimir will give them the nod. I’m sure they’re right! Vlad might even get Sergey Lavrov to deliver it personally!
P.S. Inferred no criticism of Pearls or Boyle from what you wrote.