The key issue is the extent to which infections of the Delta variant first detected in India will lead to hospitalisations and deaths. The problem is that it’s too early to say. Because of the lag between cases and admissions to hospital, many experts say a short delay could be a major benefit to understanding that relationship. “With the current knowledge about Delta, we can’t really predict the size of that wave,” said Anne Cori of Imperial College London’s modelling group. “Delaying the easing allows time to accumulate more evidence about the characteristics of Delta. And I hope in a few weeks, we would be in a better position to predict what the epidemic may look like in the next few weeks or months.”
The latest analysis suggests the Delta variant is 60% more transmissible than the previously dominant Alpha variant first discovered in Kent. The doubling time for cases is less than a week and there could be exponential growth if it is left unchecked. Cori said: “It’s hard to predict what exactly would happen if restrictions are eased as planned on 21 June. But we have used our model to explore a range of scenarios that capture these uncertainties as much as possible. In all scenarios we’ve looked at, delaying step four [of the lockdown roadmap] by a few weeks reduces the size of the wave [of cases].”
Hospital admissions and deaths
Understanding the new link between Covid case numbers and serious illness is crucial. Deaths are likely to be lower, according to Imperial’s Neil Ferguson, because more people have at least some vaccine protection and the cohort of people admitted to hospital is likely to be younger and more able to recover. However, the sheer number of cases could put pressure on hospitals and their non-Covid services. “Although vaccinations have weakened the link between cases and hospitalisations, they have not broken it entirely,” said Oliver Johnson, professor of information theory at Bristol University. His analysis suggests that “5,000 cases might convert into 200 admissions a day relatively soon”.
So far, 78% of the adult population has had at least one jab and 55% has had two – giving a high level of protection to that group, which covers a huge proportion of older people and those most at risk from serious illness. But clinicians are putting a lot of weight on the fact that a delay of four weeks could allow a significant additional number of people to have two jabs. Experts also say they want more information on just how effective the new strain is at evading the vaccine. Martin Hibberd, professor of emerging infectious disease at the London School of Hygiene and Tropical Medicine, said: “We need more information on how vaccine-resistant it is, and how much disease it causes, before we can really determine how much of a detour we need to make.”
While non-vaccinated people are now overwhelmingly the young, who tend to suffer less severely from Covid, they can get “long Covid”. The personal and medical costs of the condition could be significant, and NHS figures say there may be other effects on the young from catching the virus. Chris Hopson, the chief executive of NHS Providers, said: “We know there are significant numbers of younger people who’ve got long Covid. But also, there is emerging evidence that it could actually make someone more susceptible to long-term illness. The evidence is still very early in the making. But that would, again, be another risk here.”
The UK economy appears to be making a “quick but fragile” recovery, which means that policymakers have some leeway in deciding when to unlock, according to Carsten Jung, senior economist at the IPPR thinktank. The economy is only 4% below pre-pandemic GDP levels, according to figures published last week. “The latest lockdown hasn’t been as detrimental to economic activity as last year – we’ve become better at coping,” Jung said. That means the UK could afford, in strictly financial terms, to maintain restrictions – “although we should do what’s best for public health since that’s the best thing for the economy.” But the possibility of further lockdowns may make some businesses wary of reopening, and although consumer confidence is recovering, it still has some way to go, according to GfK, the market research firm.
There is no question that there will be a backlash from Tory MPs should Johnson go ahead with a delay to the ending of all legal limits on social contact. The Covid Recovery Group of MPs has been increasingly vocal about the need to push ahead with the end of restrictions and are likely to be vocal about the decision. However, they have no power to stop the delay and there would be no serious cabinet opposition. Rishi Sunak, the chancellor, is said to have made it clear that he would support a delay if necessary. Dominic Cummings, the prime minister’s former senior adviser, has insisted that Johnson’s personal view has been against prolonging restrictions, but officials have always insisted that they will follow the data.
Ultimately, the prime minister and his team will effectively have to rule on a difficult issue – what is an acceptable level of risk, serious illness and death from this disease? Mitigation measures may also be used, such as the wearing of masks in high-risk settings. Prof Chris Whitty, the chief medical officer for England, said at the end of last year: “We accept that in an average year 7,000 people die of flu, and in a bad flu year, 20,000 people die of flu. We accept that as what happens biologically.” Yet what might have been accepted, or ignored, by the public before the pandemic may have changed since then. Politicians and policymakers will need to make calculations about the acceptable level of risk posed by Covid, which could yet change as new variants emerge.