Currently, there is much discussion of the UK government’s vision to end all covid-19 restrictions in England on 19 July, so-called Freedom Day. This is the endpoint of the UK government’s covid-19 “roadmap.” A postponement was previously put in place because the final condition for ending lockdown—that no new variant had appeared to raise new concerns—had been missed due to steeply rising cases caused by the delta variant. As Freedom Day approaches, new cases of covid-19 are rising steeply, with projections that this may rise to 100,000 cases/day. That would be a worse trajectory than the UK’s European neighbours or the USA.
The case that the end of covid restrictions will proceed as planned on 19 July is predicated on the point that, despite the enormous caseload, this no longer carries the same ramifications as in the first two waves. The link between infection, hospitalisation, and death has been weakened by the highly successful vaccines and vaccination programme. Transmission is high, but hospitalisations and fatal cases are low. To clarify, the vaccines in use, in most people, generate good levels of neutralising antibodies and substantially reduce the chance of serious infection and death by delta after two doses. The problem is the “most people” caveat—those at the lower end of the distribution of neutralising antibodies are susceptible to breakthrough infection. [1,2] Secondary school children are currently ineligible for vaccination, and yet are susceptible to infection and have proved an excellent viral incubator during this wave. At the time of writing, concerns about the race to unlock are being raised by experts, including Mike Ryan, the WHO’s executive director for health emergencies, who has warned of the “epidemiological stupidity” of ending covid restrictions, and other leading public health experts who have published an open letter in The Lancet.
The polarisation of the debate bears witness to the fact that the cost benefit analysis is now more nuanced than in early 2021, when 1800 deaths were reported in a single day and the risks were immediate and self evident. With the UK among those countries with the privilege of relatively high vaccination levels and daily fatalities in double figures, it seems only right to ask what level of intervention is appropriate to our relationship with the virus as it is today and is likely to be in the future.
Among the arguments raised in support of Freedom Day are that we have to move on (the “now or never”), re-establish normality, and rejuvenate the economy. Israel is cited as a country achieving this, even in the face of a growing wave of delta breakthrough cases.
The difficulty is that the national situation and the interlinked global situation are far from under control. Allowing the virus freedom to circulate at high transmission levels in a partially vaccinated population is a concern. It is a real-life, population-level embodiment of viral immunologists’ laboratory experiments to model the emergence of immune-escape mutants. Such real-world vaccine escape variants are indeed starting to be sequenced [3]. The delta variant has replaced alpha as the dominant variant at present, but the possibility of other global variants coming around the curve remains. If the past 18 months have taught us anything, it is that virus outbreaks traverse the world fast, even in the face of border controls.
Lastly, there is the concern about the long term cost, in the form of new cases of long covid. We still cannot fully assess the time course of this disease process, but certainly there are hundreds of thousands of people whose lives have not yet returned to normal after more than a year. It is known that long covid ensues after SARS-CoV-2 infection, across the severity spectrum, and irrespective of asymptomatic or severe/hospitalised outcome. There is thus no reason to assume that an infection wave in a partially vaccinated population will incur less than the predicted 10-20% of all infections leading to long covid. This suggests a period in which we tolerate up to 10-20,000 people per day, many of them children and young adults, entering the pool of individuals with long covid.
It’s important to move forward, but the list of “cons” reminds us that this virus is an ongoing, formidable, and unforgiving foe, demonstrating time after time the high cost of the smallest miscalculation. This supports a case for continued caution and to go slowly and steadily with a stepwise, evidence-based easings of restrictions.
Daniel Altmann, professor, Department of Immunology and Inflammation, Imperial College London.
Rosemary Boyton, professor, Department of Infectious Disease, Imperial College London, UK & Lung Division, Royal Brompton and Harefield Hospitals, London, UK.
Competing interests: none declared.
References:
- Altmann DM, Boyton RJ, Beale R. Immunity to SARS-CoV-2 variants of concern. Science. 2021 Mar 12;371(6534):1103-1104. doi: 10.1126/science.abg7404.
- Wall EC, Wu M, Harvey R, Kelly G, Warchal S, Sawyer C, Daniels R, Hobson P, Hatipoglu E, Ngai Y, Hussain S, Nicod J, Goldstone R, Ambrose K, Hindmarsh S, Beale R, Riddell A, Gamblin S, Howell M, Kassiotis G, Libri V, Williams B, Swanton C, Gandhi S, Bauer DL. Neutralising antibody activity against SARS-CoV-2 VOCs B.1.617.2 and B.1.351 by BNT162b2 vaccination. Lancet. 2021 Jun 19;397(10292):2331-2333. doi: 10.1016/S0140-6736(21)01290-3.
- Hacisuleyman E, Hale C, Saito Y, Blachere NE, Bergh M, Conlon EG, Schaefer-Babajew DJ, DaSilva J, Muecksch F, Gaebler C, Lifton R, Nussenzweig MC, Hatziioannou T, Bieniasz PD, Darnell RB. Vaccine Breakthrough Infections with SARS-CoV-2 Variants. N Engl J Med. 2021 Jun 10;384(23):2212-2218. doi: 10.1056/NEJMoa2105000.