We now know, from bitter experience, that community-wide interventions did very little to alter the natural course of the pandemic and served only to delay the inevitable in countries such as China (once hailed as a paragon of infection control) where it was possible to seal the borders at the outset. Even a cursory acquaintance with epidemiological theory would tell you that the likelihood of interrupting the spread of an epidemic through restrictions on movement is vanishingly small.
Ivor Cummins gives an excellent talk on the history of COVID-19 to Irish Nurses and Mother’s Group.
“There are some scientists who have absolutely loved being media stars for the first time and they don’t want to stop. We don’t hear as much from the paediatricians, disease physicians, academic virologists and the immunologists who really know about these things.” (says Professor Allyson Pollock.)
Paul Hunter, professor of medicine at the University of East Anglia, said many prominent Covid voices have never written papers on infectious diseases. “It’s like me deciding, ‘I did a course on health and economics a year ago: maybe I should set up a group advising the chancellor on how to manage the tax system.’”
Professor Sunetra Gupta of Oxford University explains herd immunity, highlighting critical details about both the concept and its relevance to the COVID-19 pandemic that are often overlooked in public discussion.
The development of immunity through natural infection is a common feature of many pathogens, and we now know that COVID-19 does not have any tricks up its sleeve to prevent this from happening. If it did, it would have posed a serious problem for the development of a vaccine.
That being said, COVID-19 belongs to a family of viruses that do not typically confer lifelong immunity against infection. Most of us have never heard of the other four ‘seasonal’ coronaviruses that are currently circulating in our communities. And yet, surveys indicate that at least 3% of the population is infected by any one of these corona cousins during the winter months each year. These viruses can – and do – cause deaths in high-risk groups or require them to receive ICU care or ventilator support. Hence, it is not necessarily true that they are intrinsically milder than the novel COVID-19 virus. And like the COVID-19 virus, the other coronas are much less virulent in the healthy elderly and younger people than influenza.
One important reason why these corona cousins do not kill large numbers of people is that, even though we lose immunity and can be reinfected, there is always a sufficient proportion of immune people within the population to keep the risk of infection low for those who might die upon contracting it. Also, all of the coronaviruses in circulation — including COVID-19 — have some features in common, which means that getting one coronavirus will probably offer some protection against the others. This is becoming increasingly clear from work in many labs, including my lab in Oxford. It is against the background of acquired immunity to COVID-19 itself, as well as its close relations, that the new virus has to operate.
It is misleading to speak of “reaching” herd immunity. Herd immunity is a continuous variable that increases as people become immune and decreases as they lose immunity or die. There is a threshold of herd immunity at which the rate of new infections begins to decrease. We do not yet have a clear idea of what this threshold is for COVID-19 as the transmission landscape includes people who are susceptible to it, people who have built up immunity to it, and people who have immunity to other coronaviruses.
Unfortunately, we do not have a good way of telling how many people have been exposed to the new virus, nor how many people were resistant to begin with. We can test for antibodies but, as with other coronaviruses, COVID-19 antibody levels decline after recovery, and some people do not make them at all. Thus, antibody levels will not answer this question. More and more evidence is accumulating that other arms of immunity, like T cells, play an important role.
Indications of the herd immunity threshold having been reached in a given location are visible in the time signatures of epidemics where death and infection curves tend to either “bend” in the absence of intervention or to stay down when interventions are relaxed (in comparison with other locations where the opposite happened). Unfortunately, we do not know how far (or close) we are to that threshold in most parts of the world. This means that we need to make public health decisions based only on limited information and do so in a constantly changing environment.
Focused Protection was initially proposed as a solution for how we could proceed in the face of such uncertainty and it remains relevant now. It suggests that we exploit the fact that COVID-19 does not cause much harm to the large majority of the population and allow those individuals to resume their normal lives, while shielding those who are vulnerable to severe disease and death. We have good information about who falls into these groups and the availability of vaccines, which offer excellent protection for vulnerable populations and guard against hospitalisable illness, provide us with the ideal setting in which to implement such a plan.
Sunetra Gupta is Professor of Theoretical Epidemiology in the Department of Zoology, University of Oxford and a member of Collateral Global’s Scientific Advisory Board.
By Professor Sunetra Gupta
28 May 2021
Vaccines typically do not outperform natural immunity, so it should come as no surprise that Covid vaccines do not offer long-term protection against infection. At the same time, we can be confident that they will continue to work well to prevent severe clinical outcomes. The role of these vaccines is to offer protection to the clinically vulnerable; to foist them upon those who are at negligible risk in the hope of augmenting herd immunity is illogical…
Will boosters achieve what two doses could not? For those who are extremely vulnerable and show no evidence of mounting a significant immune response after two doses, it is entirely reasonable to attempt a third dose.
But it can be to no-one else’s individual gain to submit to a third jab, having already reduced the risk of severe disease (which was very small in the first place for most) by receiving two inoculations. For there to be the collective benefit of herd immunity, the booster would have to provide life-long protection against infection – unless we are willing to accept repeated mass vaccination into the foreseeable future. Aside from being a colossal diversion of limited resources, that would open the door to a permanent state of lockdown as we lurch from one booster campaign to the next.
Prof Bhattacharya said: “If lockdown was a primary driver of good Covid outcomes Florida would have come out far worse. It is no good to say that it did not have variants – Florida had the Alpha and Delta variant. Lockdowns don’t protect against coronavirus. And they certainly have collateral harm. Children have suffered, especially poor children. Unemployment mental health all the harm is hard to ignore and it is very hard to find any benefit to lockdown measures.”
I had no choice but to speak out against lockdowns. As a public-health scientist with decades of experience working on infectious-disease outbreaks, I couldn’t stay silent. Not when basic principles of public health are thrown out of the window. Not when the working class is thrown under the bus. Not when lockdown opponents were thrown to the wolves. There was never a scientific consensus for lockdowns. That balloon had to be popped.
…Ultimately, lockdowns protected young low-risk professionals working from home – journalists, lawyers, scientists, and bankers – on the backs of children, the working class and the poor.
Epidemiologist Prof Sunetra Gupta welcomes news that an independent inquiry will examine the government’s handling of the pandemic. “There was a religious belief that lockdowns and facemasks work. Let’s look at the costs of these strategies.”
The open letter states that “a good society cannot be created by an obsessive focus on a single cause of ill-health” and states all restrictions should be lifted in June on the final date in Prime Minister Boris Johnson’s ‘roadmap’ out of lockdown. Masks should no longer be worn by schoolchildren after May 17, say the scientists – and they warn the damage to society will be too great if the current Covid control measures continue beyond the June roadmap date.
Vaccine passports should also be scrapped along with mass community testing, they say.
Instead, the government should focus on targeted testing, creating better incentives for staying home if ill and basic hygiene measures, such as handwashing and surface cleaning.
Signatories (in alphabetical order)
Professor Ryan Anderson, Translational Science, Medicines Discovery Catapult
Dr Colin Axon, Mechanical Engineering, Brunel University
Professor Anthony Brookes, Genomics and Bioinformatics, University of Leicester
Professor Jackie Cassell, FFPH, Deputy Dean, Brighton and Sussex Medical School
Professor Angus Dalgleish, FRCP, FRCPath, FMedSci, Oncology, St George’s, University of London
Professor Robert Dingwall, FAcSS, HonMFPH, Sociology, Nottingham Trent University
Professor Sunetra Gupta, Theoretical Epidemiology, University of Oxford
Professor Carl Heneghan, MRCGP, Centre for Evidence Based Medicine, University of Oxford
Professor Mike Hulme, Human Geography, University of Cambridge.
Dr John Lee – formerly Pathology, Hull York Medical School
Professor David Livermore, Medical Microbiology, University of East Anglia.
Professor Paul McKeigue Genetic Epidemiology and Statistical Genetics, University of Edinburgh
Professor David Paton, Industrial Economics, University of Nottingham
Emeritus Professor Hugh Pennington, CBE, FRCPath, FRCP (Edin), FMedSci, FRSE, Bacteriology, University of Aberdeen
Dr Gerry Quinn, Biomedical Sciences, University of Ulster
Dr Roland Salmon, MRCGP, FFPH, former Director of the Communicable Disease Surveillance Centre (Wales).
Emeritus Professor John Scott, CBE, FRSA, FBA, FAcSS, Sociology, University of Essex
Professor Karol Sikora, FRCR, FRCP, FFPM, Medicine, University of Buckingham
Professor Ellen Townsend, Psychology, University of Nottingham
Dr Chao Wang, Health & Social Care Statistics, Kingston University and St George’s, University of London,
Professor John Watkins, Epidemiology, Cardiff University
Professor Lisa White, Modelling and Epidemiology, University of Oxford.
A year ago, there was no evidence that lockdowns would protect older high-risk people from Covid-19. Now there is evidence. They did not.
With so many Covid-19 deaths, it is obvious that lockdown strategies failed to protect the old. Holding the naïve belief that shutting down society would protect everyone, governments and scientists rejected basic focused protection measures for the elderly. While anyone can get infected, there is more than a thousand-fold difference in the risk of death between the old and the young. The failure to exploit this fact about the virus led to the biggest public health fiasco in history.
- Current lockdown policies are producing devastating effects on short and long-term public health.
- Keeping these measures in place until a vaccine is available will cause irreparable damage, with the underprivileged disproportionately harmed.
- We know that vulnerability to death from COVID-19 is more than a thousand-fold higher in the old and infirm than the young.
- COVID-19 is less dangerous for children than many other harms, including influenza.
- All populations will eventually reach herd immunity.
- Our goal should therefore be to minimize mortality and social harm until we reach herd immunity.
- Adopting measures to protect the vulnerable should be the central aim of public health responses to COVID-19.
- Those who are not vulnerable should immediately be allowed to resume life as normal.
- Simple hygiene measures, such as hand washing and staying home when sick should be practiced by everyone to reduce the herd immunity threshold.
- Young low-risk adults should work normally, rather than from home.
- Restaurants and other businesses should open.
- Arts, music, sport and other cultural activities should resume.
Dear Prime Minister, Chancellor, CMOs and Chief Scientific Adviser
We are writing with the intention of providing constructive input into the choices with respect to the Covid-19 policy response. We also have several concerns regarding aspects of the existing policy choices that we wish to draw attention to.
In summary, our view is that the existing policy path is inconsistent with the known risk-profile of Covid-19 and should be reconsidered. The unstated objective currently appears to be one of suppression of the virus, until such a time that a vaccine can be deployed. This objective is increasingly unfeasible (notwithstanding our more specific concerns regarding existing policies) and is leading to significant harm across all age groups, which likely offsets any benefits.
Instead, more targeted measures that protect the most vulnerable from Covid, whilst not adversely impacting those not at risk, are more supportable. Given the high proportion of Covid deaths in care homes, these should be a priority. Such targeted measures should be explored as a matter of urgency, as the logical cornerstone of our future strategy.
In addition to this overarching point, we append a set of concerns regarding the existing policy choices, which we hope will be received in the spirit in which they are intended. We are mindful that the current circumstances are challenging, and that all policy decisions are difficult ones. Moreover, many people have sadly lost loved ones to Covid-19 throughout the UK. Nonetheless, the current debate appears unhelpfully polarised around views that Covid is extremely deadly to all (and that large-scale policy interventions are effective); and on the other hand, those who believe Covid poses no risk at all. In light of this, and in order to make choices that increase our prospects of achieving better outcomes in future, we think now is the right time to ‘step back’ and fundamentally reconsider the path forward.
Professor Sunetra Gupta; Professor of theoretical epidemiology, the University of Oxford
Professor Carl Heneghan; Director, Centre for Evidence Based Medicine, the University of Oxford
Professor Karol Sikora; Consultant oncologist and Professor of medicine, University of Buckingham
Sam Williams; Director and co-founder of Economic Insight
Gupta, who is a professor of theoretical epidemiology at Oxford, told The Londoner that alongside huge social and educational benefits, the “evidence is mounting that early exposure to these various coronaviruses is what enables people to survive them”.
But with no sign of a second summer wave nor an autumn eruption reminiscent of 1918, the commentariat has amended the definition. Suddenly, a “second wave” meant Covid’s seasonal return, in winter, a year on. Widespread adoption of a new phrase in the Covid lexicology – “winter wave” – has academically formalised the idea.
But instead of looking us square in the eye, the Tories have chosen Big Brother’s panopticon; No 10’s new Joint Biosecurity Centre, which will drive “whack-a-mole” local lockdowns, is slickness posing as strategy – and, as it happens, reporting into track-and-trace app failure Dido Harding. When the public twigs that the infection is unlikely to be controlled in this way, the sheer panic could send us back into national lockdown. Three scenarios might help avoid the latter: a vaccine comes along; the Government gets its act together with a plan to protect the vulnerable; or we put in place safety valves against mass hysteria.
Imperial College’s research needs to be particularly scrutinised, as its international influence grows. Dr Seth Flaxman – the first author in the paper that notoriously claimed lockdowns may have prevented over 3 million deaths in Europe – this week won fresh funding to model the pandemic across several countries.
Revelations that disrupt the narrative also need to find a stronger voice: within 24 hours, the scandal of PHE’s inflated daily death figures was running out of mileage. This week’s London School of Hygiene and Tropical Medicine modelling on the impact of the pandemic on cancer deaths never gathered steam. So too a paper by Oxford’s Prof Sunetra Gupta, which elegantly combined those uneasy epidemiological bedfellows – theory and evidence – to find some parts of the UK may already have reached herd immunity.
- We have already developed herd immunity to COVID-19 and will continue to manage it through herd immunity.
- Flu is much more dangerous than COVID-19.
- COVID-19 will settle into an endemic state just like flu.
- Hopefully vaccines will be important in protecting the vulnerable.
- Another way to protect the vulnerable sector is to allow the population to develop natural immunity.
- There’s no reason to think the virus will mutate into a lower level of virulence.
- During the 1918 flu because of a large number of ‘immunologically naive’ individuals but this is not the case with COVID-19.
- Most of us have some degree of coronavirus immunity and therefore some protection to COVID-19.
- The current H1 influenza strain is antigenically identical to the 1918 flu. H1 flu doesn’t kill as many people as the 1918 flu because most people already have cross immunity.
Prolonged periods of lockdown cocooning the public from germs could leave people dangerously vulnerable to new viruses, a leading epidemiologist has warned.
Sunetra Gupta, professor of theoretical epidemiology at the University of Oxford, fears intense social distancing could actually weaken immune systems because people are not exposed to germs and so do not develop defences that could protect them against future pandemics.
“It’s becoming clear that a lot of people have been exposed to the virus and that the death rate in people under 65 is not something you would lock down the economy for,” she says. “We can’t just think about those who are vulnerable to the disease. We have to think about those who are vulnerable to lockdown too. The costs of lockdown are too high at this point.”
We spoke to Sunetra Gupta, Professor of Theoretical Epidemiology at the University of Oxford and head of the team that released a study in March which speculated that as much as 50% of the population may already have been infected and the true Infection Fatality Rate could be as low as 0.1%.
In her first major interview since the Oxford study was published, she goes further by arguing that Covid-19 has already passed through the population and is now on its way out. She said:
• Many of the antibody tests are “extremely unreliable”
• They do not indicate the true level of exposure or level of immunity • “Different countries have had different lockdown policies, and yet what we’ve observed is almost a uniform pattern of behaviour”
• “Much of the driving force was due to the build-up of immunity”
• “Infection Fatality Rate is less than 1 in 1000 and probably closer to 1 in 10,000.”
• That would be somewhere between 0.1% and 0.01%
On lockdown policy:
• Referring to the Imperial model: “Should we act on a possible worst case scenario, given the costs of lockdown? It seems to me that given that the costs of lockdown are mounting that case is becoming more and more fragile”
• Recommends “a more rapid exit from lockdown based more on certain heuristics, like who is dying and what is happening to the death rates”
On the UK Government response:
• “We might have done better by doing nothing at all, or at least by doing something different, which would have been to pay attention to protecting the vulnerable”
On the R rate:
• It is “principally dependent on how many people are immune” and we don’t have that information.
• Deaths are the only reliable measure.
On New York:
• “When you have pockets of vulnerable people it might rip through those pockets in a way that it wouldn’t if the vulnerable people were more scattered within the general population.”
On social distancing:
• “Remaining in a state of lockdown is extremely dangerous”
• “We used to live in a state approximating lockdown 100 years ago, and that was what created the conditions for the Spanish Flu to come in and kill 50m people.”
On next steps:
• “It is very dangerous to talk about lockdown without recognising the enormous costs that it has on other vulnerable sectors in the population”
• It is a “strong possibility” that if we return to full normal tomorrow — pubs, nightclubs, festivals — we would be fine.
On the politics of Covid:
• “There is a sort of libertarian argument for the release of lockdown, and I think it is unfortunate that those of us who feel we should think differently about lockdown”
• “The truth is that lockdown is a luxury, and it’s a luxury that the middle classes are enjoying and higher income countries are enjoying at the expense of the poor, the vulnerable and less developed countries.”