Sunday, December 05, 2021

More vaccinated people are dying than unvaccinated people?

Some official British statistics say so. I first noted the problem a couple of weeks ago but could not see where the problem lay. I suspected a sampling problem but could not see where it was. The graph I saw at that time is below:

image from

I do now however understand it, courtesy of the post below. Let me see if I can put it in a clearer way.

If the vacine is only 90% effective, there SHOULD be many cases of vaccinated people getting ill. 10% is a lot of people. So the vaccinated who get ill are drawn from an unfortunate remnant of vaccinated people -- only 10% The vaccinated people who get the virus ARE NOT TYPICAL of vaccinated people. So comparing their numbers with unvaccinated people is not a valid comparison. The vaccinated people who get the virus are not a fair sample of all vaccinated people.

So that explains the large number of vaccinated people becoming ill. Why do so few unvaccinated people become ill? Initially because they a minority of the population but mainly because of who they are. They will almost always be people who feel their health is good and that it will beat the virus by itself. And people who feel in robust health will almost always actually be in robust health. And the small number who get the virus show that they ARE mostly in robust health and so few of them die.

So the two populations are very differently selected so are not comparable

The latest data published by the UK Health Security Agency shows that of 3,726 COVID-19 deaths over a three-week period to November 21, 2,903 were people fully vaccinated against the disease, compared to 708 unvaccinated people.

However, those figures do not mean that vaccinated people are at a higher risk of death from COVID-19.

The UK report also provides the rate of death per 100,000 people in each group.

That data reveals that the rate of death among unvaccinated people across the UK was higher for every age bracket when compared to those who were double-dosed.

According to Tony Blakely, an epidemiologist at the University of Melbourne, when it came to being infected with the Delta variant of coronavirus, fully vaccinated people were around 90 per cent less likely to die than those who weren't vaccinated.

"We can say mathematically if vaccination reduces your chance of death by, say, 90 per cent, then once more than 90 per cent of the population is vaccinated you would expect the [number of] deaths among the vaccinated and unvaccinated to be similar," Professor Blakely said in an email.

He noted that high rates of natural COVID-19 infection in the UK community added complexity.

"For example, if 90 per cent of the population are vaccinated and, of the remaining 10 per cent half of them (that is, 5 per cent of total population) have already had a natural infection, they will be better protected than the vaccinated," he explained.

"So, because an increasing fraction of the unvaccinated have had an infection in the past, this will tip more of the infections, hospitalisations and deaths to be among the vaccinated.

"But the bottom line remains — the unvaccinated have a much much higher chance of death on their first infection than do the vaccinated."

Additionally, in footnotes attached to its data, the UK agency notes that vaccinations were prioritised for individuals who were more vulnerable to catching COVID-19, while "individuals in risk groups may be more at risk of hospitalisation or death due to non-COVID-19 causes, and thus may be hospitalised or die with COVID-19 rather than because of COVID-19".


Omicron is being grown in labs and studied as scientists race to unlock the COVID-19 variant's mysteries

Every day for the last week, Thumbi Ndung'u and his team of researchers have spent hours inside a room with the world's most feared coronavirus variant.

To keep themselves from becoming infected, they pull on white plastic cover-alls and wear industrial respirators slung around their waists.

While the rest of the world braces for the possible spread of the new Omicron variant, Professor Ndung'u is doing something seemingly counterintuitive: He's growing it in a laboratory.

His team is among a vanguard of scientists across the world racing to examine the mysterious new variant under tightly controlled conditions to understand how it behaves.

Omicron, more a distant cousin than a direct descendant of the Delta variant, has strange and concerning features.

In the worst-case scenario, this evolution could mean a more transmissible version of COVID-19, with the ability to evade existing vaccines.

For Professor Ndung'u, a Kenya-born Harvard-educated virologist from the Africa Health Research Insitute in Durban, none of that is certain until he and his colleagues do their work.

"What we have been doing so far is speculate," he said.

"This is a very important next step."

The three big questions about Omicron

Although the variant has already driven governments the world over to slam borders shut and healthcare systems to bristle, there is still remarkably little known about Omicron.

What began with reports of a new variant first identified in Botswana and South Africa late last month has now grown to a smattering of cases in Europe, the US and Australia, where authorities remain on high alert.

There are three key questions about the variant that are yet to be answered: How transmissible it is, how effective current vaccines will be against it, and what severity of symptoms it might cause in those infected?

In the absence of much real-world data on how Omicron affects human populations, laboratory testing is needed to see just how dangerous it is.

But the world is in for an anxious wait. Results may still be some weeks away.

For Professor Ndung'u and his team, unlocking the secrets of the variant is what they do best.

"From a scientific point of view, it's exciting," he said.

Even so, some South African doctors who have treated patients infected by Omicron are adamant the variant is different to what they have encountered in previous waves, though there is not enough data yet to decide that.

Angelique Coetzee, a GP at a family practice in Pretoria, was among the first to raise the alarm over Omicron with South African authorities last month.

So far, Dr Coetzee estimates she has seen about 30 patients infected with Omicron come through her clinic.

Her experience with Omicron is anecdotal, but she does have cause for cautious optimism.

"The majority of patients that we are seeing have mild symptoms," she said

"Most of the adults will phone us [after they recover] and say they are so much better. This is not something that you would see with the Delta variant."

One mystery that will likely take more time to solve is where Omicron originated.

Although it was first detected in Botswana and South Africa, earlier cases have since been reported in other countries.

Some have speculated it could have mutated inside a person with an already weakened immune system because of an HIV infection.

The immunocompromised tend to have viral infections persist for longer, increasingly the likelihood of a mutation occurring.

It's possible that higher rates of HIV in southern Africa, coupled with low COVID-19 vaccination rates, could have created an environment where the new variant was more likely to mutate. But there is simply no evidence this has actually happened, according to Professor Ndung'u.

"At the moment, I think the scientific evidence for that is sketchy," he said.

"But it's certainly a very important issue because of the fact that we have high HIV infection rates in southern Africa."

The rise of a new variant has forced experts in wealthier countries, including the United States, to reconsider the need of booster shots where previously they had been wary to endorse them without further evidence.

Australian authorities say they won't speed up the booster program for most people, despite Omicron concerns.

In Israel, the first country to widely distribute booster shots to teenagers and adults, the population might enjoy much better immunity to Omicron, said Professor Nadav Davidovitch, a public health physician at Ben Gurion University.

"Israel has an excellent vaccination campaign, so in this sense we are better prepared," he said.

"Probably the vaccine won't be exactly covering the variant. But there will be some coverage for sure."




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