The ‘stylized facts’ concerning vaccine effectiveness against Covid are as follows. First, the vaccines confer strong protection against infection, which peaks about one month after the second dose. However, this protection then wanes over the following five or six months to as low as 20% (or even lower).
Second, the vaccines also confer strong protection against serious illness and death, and this protection wanes much more slowly. Hence, six months after vaccination, the vaccinated still have substantial protection against death.
While these stylized facts are approximately right, there’s reason to believe that vaccine effectiveness against death has been overestimated. Note: by ‘overestimated’ I simply mean that effectiveness may be somewhat lower than is claimed, not that effectiveness is zero (or even close to zero).
The reason effectiveness against death may have been overestimated was highlighted in a recent study by the U.S. CDC. Using data on a large cohort of Americans, Stanley Xu and colleagues calculated non-Covid death rates (adjusted for age and sex) among vaccinated and unvaccinated persons.
Their findings are shown in the figure below (taken from the Economist). Notice that, on both charts, the light blue bar is much higher than the other two bars, indicating that non-Covid death rates were substantially higher among the unvaccinated.
The researchers interpreted their results as evidence of vaccine safety. (If the vaccines were very unsafe, you’d expect a lot more non-Covid deaths in the vaccine groups.) However, there’s another implication, which the researchers also acknowledge: people who get vaccinated tend to be healthier and/or more risk-averse than those who don’t.
How do we explain this ‘healthy vaccinee’ effect? There are at least two possibilities. First, some people may be too frail to get vaccinated, due to old age or underlying health conditions. Second, some people may just be inherently healthier/more risk-averse, and as a result may be more likely to get vaccinated and less likely to die of other causes.
The CDC researchers actually attempted to control for the healthy vaccinee effect by selecting unvaccinated persons from among those who’d had at least one flu shot in the last two years. The fact that they still observed a difference in death rates suggests the true effect may be even larger.
While the CDC’s results might be good news from the perspective of vaccine safety, they’re bad news from the perspective of vaccine effectiveness.
Suppose you do a study, and find that the Covid death rate is ten times higher among unvaccinated people than among vaccinated people. That difference could be due to the vaccines. But it could also be due to the fact that vaccinated people are less likely to die for any reason.
Observational studies of vaccine effectiveness do attempt to control for the healthy vaccinee effect, for example by including some measure of health/frailty as another variable in the analysis. However, these kinds of measures may not capture all the relevant differences between vaccinated and unvaccinated people.
Consider Israel. By the start of June, the country had fully vaccinated 55% of its population (and an even higher percentage of adults). Despite this, and despite having gone through two previous waves of Covid, the country saw a major third wave associated with the Delta variant. Here’s the chart of daily Covid deaths:
One might have assumed that natural immunity from the two previous waves, combined with a 55% vaccination rate, would have kept deaths to a minimum. Yet the number of deaths was still substantial, at least relative to the previous waves. This is particularly evident if we look at excess mortality:
Total excess mortality in Israel’s third was about the same as in its first wave, and was actually higher than in its second wave. Now, it’s true that a disproportionate share of Covid deaths were among the unvaccinated. But this is consistent with the healthy vaccinee effect.
Of course, I’m not claiming that a plot of excess mortality in one country constitutes a serious analysis. Mortality would presumably have been higher absent the vaccination campaign. However, it’s hard to reconcile the chart above with claims of, say, 90% effectiveness against death.
To repeat: I’m not claiming the vaccines aren’t effective against serious illness and death; only that their effectiveness (after two doses) may have been overstated. Offering the vaccine to over 50s still makes sense as a way to achieve focused protection.
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Blar Blar Blar! Self important tw*ts!
It is not made clear why carbon neutrality is the concern of a group dedicated to diversity, equity and inclusion
That’s absolutely clear: Just Like COVID-19 and systemic racism, it’s part of the same pseudo-revolutionary scam by the same (kind of) people. They have some set of policies they want to see implemented (like favoritism towards groups they want associate with), some set of fortunately silent (or even yet unborn) pitiful victims on whose behalf they claim to be speaking (like the poor and oppressed or our childrend and grandchildren) and some ill-defined problem with supposedly apocalyptic consequences which urgently needs to be addressed.
The only sensible way to deal with this is to reject it. The purposes of politics is to improve the present and not, to solve problems of future generations before they even manifest themselves. Future generations will have to look after themselves once the time has come for that, they’re going to face problems we don’t have an idea of yet and will address them with means which haven’t been invented so far. People who are permanently stuck in the middle of the 20th century ought to consider relegating themselves to museums instead of claiming their ever more distant past would really be the future.
If you go back to 1923 it would be impossible to predict what 2023 would look like. —–The Internet. Aeroplanes, Cars, Lighting, Gas central heating, Massive rise in life expectancy, Freedom from preventable diseases, Appliances to bring an end to back breaking labour etc etc etc etc. Trying to pretend you want to decarbonise for the benefit of future generations that will be 3 times wealthier than we are is mealy mouthed eco posturing that tries not to admit what climate change policies are really about, and they are mostly not about the climate. The amount of politicians who bleat about their “children and grandchildren” is vomit inducing. Especially as these same pretend to save the planet people are doing their best to remove the very fuels they will need to have the standard of living their grandfathers and grandmothers currently have. because you cannot power industrial society on wind, sun, hydrogen or tidal. Constant brainwashing today has a whole generation of young people who are clamouring for their own impoverishment and infact they glue themselves to the road and “demand” it.
“Trying to pretend you want to decarbonise for the benefit of future generations that will be 3 times wealthier than we are is mealy mouthed eco posturing…”
On current trajectories and unless we stop the Davos Deviants one thing I can absolutely guarantee is that future generations WILL NOT be three times wealthier than we are, three times poorer most probably.
What is having a “disproportionately harmful effect on the poor and the oppressed” is denying them fossil fuels. One billion people in the third world have no electricity. ——–Just take a moment to contemplate that. ————NO ELECTRICTY.— This is a diabolical disgrace. The EU (climate activists supreme) at one point spent vast sums on the idea that they could cover the Sahara in Solar Panels and import that electricity back into Europe. What a total smack in the face for the worlds poorest. The phony planet savers would deny these poor people access to fossil fuels that would bring them out of the abject misery of a stoneage existence, and then steal their sunshine and cable it all back to the wealthy EU.
And denying them food by closing down productive farms in western countries.
And trying to reduce CO2 (plant food) levels to reduce crop yields, even though this is not possible.
Talking of heights of absurdity, yet possibly sound business sense and an eye for money…
By co-incidence, an advert appeared today in my inbox for Boom Technology, which is seeking share capital and other funding to re-introduce supersonic flight. The brochure ingeniously leverages the customer desire for all things Green, by explaining how really expensive the pre-Green fuel bill was for supersonic flight, yet somehow fudges the issue of how Green fuel is even more expensive than aviation kerosene. Presumably the target customer base is rich Green virtue-signallers who will be persuaded that they are Saving The Planet by flying supersonic, “because it’s Green, innit?” Presumably government employees will also be encouraged to fly the green flag by going supersonic whenever possible, especially if they are Important People.
Assuming this is not mere pamphletware and prospectus fluff, I wonder where the money will actually come from? Will it be from early investors and government funding rather than customers, rather like domestic solar panels and windfarm owners? Who will keep it financially aloft when the Green Mania wears off, like the Railway Mania faded in the late 1840s ?
… which reminds me. Railway Mania was partly the invention of new technology but also partly the result of collusion between MPs and venture capitalists that caused all manner of Acts of Parliament to be passed to support building railways, some brilliantly conceived, some hopelessly economically, some unfortunate gambles, and some outright fraud on investors. Surely MPs these days don’t stoop to taking bribes, or aren’t just gullible dupes, to support massive financial scams perpetrated on small investors and the general public….???
But didn’t I read somewhere that internet servers worldwide use about 10% of all generated electricity, so putting stuff on-line only contributes to the need for that power and despite what claims are made, not all of it is “green”. Please correct me if I’m wrong.