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Rapid response to:


Covid-19: Experts divide into two camps of action—shielding versus blanket policies

BMJ 2020; 370 doi: (Published 21 September 2020) Cite this as: BMJ 2020;370:m3702

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Rapid Response:

COVID-19: open, reasoned, detailed, discussion of the options is overdue and welcome

Dear editor,

COVID-19: open, reasoned, detailed, discussion of the options is overdue and welcome

At last, differing perspectives are being aired. This is healthy. People are mostly well educated and understand the situation, and are stoical. They and their elected representatives in Parliament must no longer be sidelined. We must hear their voice. However, there is no reason to divide into camps, and I do not see myself as being in one. As one of those calling for public debate and involvement including on the issue of population immunity, a phrase which should replace herd immunity for human populations, I welcome this exchange of knowledge and opinion. (1)

Population immunity is, inevitably and unavoidably, one, albeit limited strand of a comprehensive public health strategy. (1) Whether the proportion of the population infected is 5%, 10% or 20% this helps reduce spread. (2) No one is advocating “letting the infection rip”, a phrase only heard from the lips of people who do not want this discussed.

I support an approach that accepts that, over some time, most young people will get the infection as they return to normal life through schooling, starting new jobs, and going to university. (1) Children and young people generally have strong defences against this infection,(3) although morbidity and mortality occur rarely, but less so than other infections like influenza. (4-6) These risks have to be offset against the educational, social and other problems of lockdown and related measures.

Immunity is strong following infection, given that several hundreds of millions of cases of COVID-19 have surely occurred and a handful of people have had the infection twice ( accessed 21/9/2020). In calculating this number I assume an infection fatality rate of 0.5% and the number of deaths as at least 2 million, giving 400 million people infected. Readers can insert their preferred numbers to reach their own conclusions on the true number of cases worldwide. Even if 1 million cases had been recurrent infections, not a handful, this would be a small number, indicating strong immunity. It would be truly extraordinary, perhaps unique in the history of medicine, if immunity was hundred percent and lifelong after this infection.

Vaccines will not be proven to be safer for children and young people than the infection for some years, if ever. Two adenovirus-based vaccines have already been shown to have important side-effects that mimic COVID-19 infection -- i.e. fever, pain, fatigue and headache. (7, 8) the side-effects have been glossed over. The side effects are occurring in 70-80% of fit people in the young adult and middle age groups. We really must know whether it is effective in people over 70 years. A vaccine is not going to be a panacea. There will be resistance and it will be contested, including in the courts, as by sheer coincidence people will die or become seriously ill shortly after receiving the vaccine and will blame it.

A strategy based upon the careful acquisition of population immunity through natural infection in young, low-risk people requires special efforts directed at those at high risk of any age group, including the young. (1) No-one is advocating this as the sole strategy or even the ideal one. These ideas have been conceptualised (9) and modelled (10,11) but have been too readily dismissed, even rendered taboo. Yet, the concept engenders enormous support from the public (well over 90% in my experience) and many professionals and seen as simply common sense. I have discussed my COVID-19 zugzwang paper in numerous forums, including in-depth interviews ( , I have also had several grillings by seasoned BBC journalists. I expected to be vilified, but the opposite has happened. Huge numbers of people, worldwide, have expressed their support. They have told me that they have similar views but were not able to express them until a seasoned public health professional like myself had done so.

Let me summarise my view: children and young people have a great deal to lose from measures that restrict their education, social development and freedom and have relatively little to lose from the infection. Older people like myself (67 years of age, retired, married and an Indian male) have little to lose from restrictions. Indeed, several friends and colleagues have welcomed them as a restful period when they become more prosperous. I have much to lose from the infection. Nonetheless, I am not prepared to sacrifice the well-being of children and young people for society to try to reduce my risk to zero, which is near impossible until the virus is vanquished worldwide. I believe society should concentrate the scarce resources we have to protect those who are frail or for other reasons cannot protect themselves. People in a privileged position like myself have to apply well-known solutions: hygiene, social distancing and face masks.

The problem is not going away with and without a vaccine. Our vision and strategies should be long-term, not week by week. Dismissing any idea, no matter how zany it might seem, without detailed and reasoned discussion, is irresponsible at this time of global crisis.

1. Bhopal RS. COVID-19 zugzwang: Potential public health moves towards population (herd) immunity. Public Health in Practice. 2020;1:100031.
2. Fine P, Eames K, Heymann DL. “Herd Immunity”: A Rough Guide. Clinical Infectious Diseases. 2011;52(7):911-6.
3. Carsetti R, Quintarelli C, Quinti I, Piano Mortari E, Zumla A, Ippolito G, et al. The immune system of children: the key to understanding SARS-CoV-2 susceptibility? The Lancet Child & Adolescent Health. 2020 10.1016/S2352-4642(20)30135-8.
4. Bhopal S, Bagaria J, Bhopal R. Children's mortality from COVID-19 compared with all-deaths and other relevant causes of death: epidemiological information for decision-making by parents, teachers, clinicians and policymakers. Public Health. 2020;185:19-20.
5. Bhopal SS, Bagaria J, Olabi B, Bhopal R. COVID-19 deaths in children: comparison with all- and other causes and trends in incidence of mortality. Public Health. 2020.
6. Götzinger F, Santiago-García B, Noguera-Julián A, Lanaspa M, Lancella L, Calò Carducci FI, et al. COVID-19 in children and adolescents in Europe: a multinational, multicentre cohort study. The Lancet Child & Adolescent Health.
7. Zhu F-C, Guan X-H, Li Y-H, Huang J-Y, Jiang T, Hou L-H, et al. Immunogenicity and safety of a recombinant adenovirus type-5-vectored COVID-19 vaccine in healthy adults aged 18 years or older: a randomised, double-blind, placebo-controlled, phase 2 trial. The Lancet. 2020;396(10249):479-88.
8. Folegatti PM, Ewer KJ, Aley PK, Angus B, Becker S, Belij-Rammerstorfer S, et al. Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, single-blind, randomised controlled trial. The Lancet. 2020;396(10249):467-78.
9. Smith GD, Spiegelhalter D. Shielding from covid-19 should be stratified by risk. 2020;369:m2063.
10. van Bunnik BAD, Morgan ALK, Bessell P, Calder-Gerver G, Zhang F, Haynes S, et al. Segmentation and shielding of the most vulnerable members of the population as elements of an exit strategy from COVID-19 lockdown. 2020:2020.05.04.20090597.
11. McKeigue PM, Colhoun HM. Evaluation of "stratify and shield" as a policy option for ending the COVID-19 lockdown in the UK. 2020:2020.04.25.20079913.

Competing interests: No competing interests

23 September 2020
Raj Bhopal
Emeritus Professor of Public Health
The University of Edinburgh
Medical School, Teviot Place, Edinburgh EH8 9AG