November 25, 2021 - 3:53pm
Neil Ferguson says he thinks we’re “almost at herd immunity” in Britain. Herd immunity is when enough people are immune to the virus — via vaccination or infection — that the disease cannot increase in prevalence, and either becomes stable or dwindles away.
Is he right? Well, I hope so, because I said something similar myself a few weeks ago, but I’d still be cautious. Let’s have a quick look at some basic numbers.
First, the naive way of calculating a herd immunity threshold uses the R0 of a pathogen — the number of people that each infected person would infect if no one had any immunity. If the R0 is five, then the herd immunity is one minus a fifth, or 80%. The R0 of the Delta Covid variant is probably about five, so (again, naively) herd immunity is about 80% coverage.
The Office for National Statistics’ Covid infection survey suggests that about 92% of the adult population would test positive for antibodies — that is, has either had the disease, been vaccinated, or both. That sounds good, but 92% of the adult population is only about 74% of the total population. About a fifth of Britons are children.
But a lot of children (including my eldest!) have had Covid. The Cambridge MRC Biostatistics Unit estimates that about five million, or 80%, of five- to 14-year-olds have had the disease, and on top of that, a bit less than half (you can get the data here) of 12- to 15-year-olds have been vaccinated. Maybe that’s an overestimate, but we can confidently say that more than half of children have some immunity. On this naive calculation, then, we have very likely reached the herd immunity threshold, probably with a bit to spare.
There’s a complication, which is that “immunity” isn’t binary. I know lots of people who’ve had the vaccine but still got Covid; they’ve generally been fine, at worst having a nasty flu-like condition for a few days. But they still got it. The vaccine reduces your risk of getting the virus, and your risk of getting very ill if you do, but it doesn’t reduce it to zero. We can’t just say “90% have been vaccinated or had the disease, ergo we’re at herd immunity”. That said, Ferguson’s guess that we’re near it seems plausible.
It makes sense because we opened up so much earlier than other countries, meaning that we’ve gained a lot more immunity through infection (at the expense of a lot of lives lost). And it certainly would explain the wobbly plateau of case numbers that we’ve seen for the last few months.
But here’s the note of caution. Herd immunity isn’t a fact about the virus: it’s an interaction between the virus and our behaviour. As an epidemiologist told me the last time I wrote about Covid case numbers, it’s much harder to predict the course of a pathogen when R is near 1. You can get unpredictable outbreaks in local patches, sub-populations with lower vaccination levels. Minor behaviour changes (more people socialising indoors as it gets colder? Christmas?) can push R up and alter things significantly.
In response to that piece of mine, the forecasting site Metaculus put together some predictions for what was going to happen in the coming months — will we have further restrictions like Plan B or something more extreme; how high will the number of people in hospital get over winter, that sort of thing.
Metaculus’s forecasts have a pretty good record in the pandemic so far. They think that Plan B-style restrictions are more likely than not before February 2022, and that there’s a good chance (≈25%) of more stringent ones, including a ban on household mixing at Christmas (≈20% chance). They also think that hospitalisations are likely to go up fairly significantly from their current level. (You can see their other relevant predictions here and here.)
So while we may be at or near herd immunity, we’re also in a knife-edge situation where changes in behaviour could change things quite a lot, and change the threshold for what counts as herd immunity. Numbers could still go up, and we could still see ourselves facing restrictions. I think it’s vanishingly unlikely that we’ll see anything like last winter’s numbers. But this winter could still have some unpleasant surprises in store.
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Subscribe“Professor Neil Ferguson believes”
Good point and enough said.
Ferguson… isn’t he the guy who was the model for the painting ‘The Scream’ by Edward Munch?
Oh dear….not Neil again.
~ written on a local bathroom cubicle
Tee hee
I went to the comments to post this and found you got here first. It’s beyond belief that the media are still quoting Ferguson when he’s been wrong about everything *and* he’s a hypocrite who broke the lockdown rules he claimed were necessary for everyone else.
And Tom Chiver writes ……. Again
All you need to know about Neil Ferguson can be gleaned from this exposition of his cherry-picking – http://www.pseudoexpertise.com/clarke-covid3.pdf and http://www.pseudoexpertise.com/cherry.pdf
When did ‘herd immunity’ become rehabilitated; it was always wrongly a term treated with contempt by the pro-lockdown cabal?
This was stated by Prof Sunetra Gupta (someone terribly abused by the same people) today:
“It is my opinion that repeated exposure to related influenza strains has so far averted a pandemic of the proportions of the devastating pandemic of 1918. Prior to 1918, influenza most likely died out completely within inter-pandemic periods. Since the previous influenza pandemic had occurred in 1890, most individuals under the age of 30 had no experience of it and they are the ones who died.”
According to the ONS there have been about 1500 excess deaths each week for the past four months. This trend shows no sign of easing up. Only about half of these deaths are likley to be directly caused by COVID, Many are due to thrombosis or inflammation in the cardiovascular system.
What is going on? What might have caused an increased risk of inflamation or thrombosis in the heart or veins?
Covid perhaps? I’d imagine any virus that in the worst case scenario leaves patients needing forced oxygen to breathe could put a strain on the heart and blood supply due to drop in oxygen levels in smaller doses
SHOCKING video from the world’s most liked and respected Covid youtuber – Dr Campbell, he has resolutely remained pro mask and vax throughout – although he covers alternate issues purely by reading the results of studies – as he does today:
https://www.youtube.com/watch?v=LEBGl8MVE-c
100%+ increase in heart attack risk indicators for people after the vax – check it out, although as he keeps pointing out, this is not Peer Reviewed, but pretty wild – worth a look. It is based on 500 people being monitored for heart problems prior to getting their vax – then after. Before they were half the indicators of the heart issues the study measures, doubling after vaxxing….
A nice guy for sure, but he very rarely gives proper credit to scientists who are doing amazing work at trying to get out the truth of what is really happening. He is pretty much an NHS/Govt/Big Pharma puppet, who will VERY occassionally be a bit radical and mention something like myocarditis, vit d, ivermectin, but he doesn’t do a deep dive, but yet will talk endlessly about deaths, masks, and variants. He is also very poor at analysing statistical data that does not tow the line of big pharma et al.
Paul – try this dr Campbell on Vax complications, very watchable https://www.youtube.com/watch?v=H7inaTiDKaU
and here is his Ivermectin Mata-study which shook op the world https://www.youtube.com/watch?v=3j7am9kjMrk
I think your statement that “the vaccine reduces your risk of getting the virus” may need some supporting evidence. I haven’t seen many robust studies that have come to this conclusion, and a recent paper in the lancet showed the attack rate in households was identical, regardless of vaccination status.
In general we need to look a lot further upstream going forward. How can we make the population healthier and more resilient in the face of new pathogens instead of reaching for the sledgehammer approach of lockdowns.
You seem to have identified 1 study which argues against protection and have managed to miss all the other studies demonstrating protection, starting with the very first trial on the BioNTech vaccine in November 2020. I suspect you might be a tad biased!
And his upvoters too – but that’s Unherd.
Yes, I think vaccination offers a reasonable level of protection in the community, especially against serious illness. However, I think it’s not so effective against transmission within a household
Ferguson was behind the disputed research that sparked the mass culling of eleven million sheep and cattle during the 2001 outbreak of foot-and-mouth disease. He also predicted that up to 150,000 people could die. There were fewer than 200 deaths
In 2002, Ferguson predicted that up to 50,000 people would likely die from exposure to BSE (mad cow disease) in beef. In the U.K., there were only 177 deaths from BSE.
In 2005, Ferguson predicted that up to 150 million people could be killed from bird flu. In the end, only 282 people died worldwide from the disease between 2003 and 2009.
In 2009, a government estimate, based on Ferguson’s advice, said a “reasonable worst-case scenario” was that the swine flu would lead to 65,000 British deaths. In the end, swine flu killed 457 people in the U.K.
Last March, Ferguson admitted that his Imperial College model of the COVID-19 disease was based on undocumented, 13-year-old computer code that was intended to be used for a feared influenza pandemic, rather than a coronavirus. Ferguson declined to release his original code so other scientists could check his results.
No human beings died of FMD. The only human death directly caused by the outbreak was a slaughterman killed with a captive bolt pistol. There were probably suicides of business owners bankrupted by the closure of the countryside and tourism.
FMD rarely kills animals. It is an economic plague. It is controlled by slaughter to stop herd immunity developing. Meat with FMD antibodies is worth less in foreign markets.
The response to an economic plague in farmed animals has wholly different objectives to the response to a human virus. They cannot be compared.
Ferguson played his crucial role at the start of the SARS-CoV-2 pandemic, and helped the world plunge into a mass psychosis it still hasn’t got out of. He can now do as he pleases. His part is over, money’s coming in steadily.
It is impossible to have herd immunity to a virus that people can catch more than once. It is possible to have herd resilience. We have that to the other common cold viruses and we soon will to this.
Well said! Its time the fear and hype surrounding this coronavirus was put to bed. . Although many people have died (with Covid MENTIONED on their death certificate) it is less than 1% of our population and a large number of those already had life-threatening illnesses or had reached the end of their lifespan.
But we can’t make a judgment about this until we know the extra deaths that have occurred during the last eighteen months. Have we been given this? I have not heard..
Yes, I agree, herd immunity is not going to happen, even with the vaccine (especially with far from 100% vaccination)
Don’t mutations have to figure in this somehow? We could be at herd immunity for Delta but nowhere near that for this new Botswana variant?
Yes, all bets may well be off. If this variant goes on the rampage, it will be interesting how politicians react. More lockdowns? Flights are already blocked
If it is far less lethal, it won’t matter.
Yes, there are mutations that may make it more transmissible, but it might turn out to be less dangerous. Is that not in line with long-term predictions?
What about these latest mutations which may be able to bypass immunity? This is not reflected in the R number model, and even with high levels of vaccination etc we could see massive growth in these variations… Then what happens to herd immunity?
Nobody knows.
Only the ‘Bat Lady’ can answer your question, and she is on holiday in a Resort Camp in Xinjiang with some of her Uyghur buddies. She is not expected back soon.
The entire response has been so weirdly handled that Conspiracy is the only answer I can believe. Medically, Economically, and the totalitarian ending of all freedoms and replacing them with Martial/Civil Law, this is WEF/Davos and Great Reset territory. .
First is how study of existing Medicines has been prohibited by the organizations who fund medical research. A very great deal can be found on-line on how Fauci and his minions (as head of the world’s largest medical research, NIH he not only decides how, and who, get funding for research – he must be obeyed or you will never get funding in the future, according to the web) Then the FDA and CDC, and the state CDCs all have become 1st Political, then a tool of the medical/Pharma Industrial Complex (The heads of the regulatory, and the industry, switch between the two), back and forth, then they are a jobs program (so all must do as told to ride the gravy train).
“Japan sees huge drop in cases after it switches to IvermectinThe head of the Tokyo Medical Association appeared on national television in September urging doctors to use Ivermectin and they listened. A little over a month later, Covid-19 is under control in Japan.” Yet all Western Medical have been prohibited from proper studies on this, and Fluvoxamine and all the other Medicines.
Vax has been the only allowed response! To get herd immunity without medicines and prophylaxes medicines is useless during a pandemic. Bret Weinstein goes on about this – as do a very great many qualified people. Dr Campbell stays correct – but does many shows on this saying how effective studies show some medicines – if repurposed – are at stopping covid, and how Western studies are blocked.
Social Media has done a full censoring Block-out on discussion on medicines. Google Ivermectin and you are drowned out by trash articles saying how bad it is, and how dangerous it is to use for covid… But under there are thousands of great studies, hidden by the algorithm. Social Media has forbidden any but the official line to be shown – Why? Same as MSM, 100% they are government mouthpieces.
Here is JP Sears doing a hidden camera documentary on FDA and a Pharma rep in action…. (I suspect it is satire, but can’t be sure as the evidence points this direction). https://www.youtube.com/watch?v=Czu11HmhfAY
Chivers, how about using your great numbers brain to look behind the curtains and see if anything is odd back there? Start by watching Dr Campbell on youtube, all the ones with studies…..
As a biologist I really rate Dr John. And the comments come at him from BOTH sides so he must be doing something right. He’s also a really good teacher. Suppression of studies on Ivermectin are one of the greatest evils of the Big Pharma lobby the new drug which acts in the same way $500 approximately for a week, out of patent ivermectin $2.
The publisher has now marked the Abstract 10712 “We are publishing this Expression of Concern until a suitable correction is published to indicate that the abstract in its current version may not be reliable.”
Oh dear. Looks as though we are nowhere near herd immunity then
I’ve got three words for you, Tom: ‘Vaccine’ efficacy wanes.