It was the moment the scientists veered off script. As ministers moved to ease the lockdown in late May, a handful of the government’s advisers from Sage (the Scientific Advisory Group for Emergencies) went public with their fears. The virus was still a present danger, infecting thousands of people a day, they warned: now was not the time to lift the lockdown.
As others came out in support of the experts, it seemed most scientists were of one voice. But that is not the case. Sunetra Gupta, a professor of theoretical epidemiology at Oxford University, believes – somewhat controversially – that the lockdown should be lifted faster. In the rush to drive infections down, she fears the poorest have been brushed aside.
“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.”
Gupta is not one of the scientists whom the epidemic has made a household name. But on 26 March, the day the lockdown came into effect, she intervened with research that made instant headlines. Her team at Oxford used a simple susceptible-infected-recovered (SIR) model to produce a best-case scenario for the outbreak as a counterpoint to the government’s worst-case scenario.
The worst case, adopted by government, was that left unchecked, the virus was so dangerous the epidemic could claim 500,000 lives. The best case, set out by Gupta, is not currently borne out by scientific data – but she insists it is an important consideration and counterbalance.
Gupta’s model showed that if the virus had arrived in Britain a month earlier than thought – in December rather than January – it might have spread far wider than anyone appreciated, and infected half the population. If that was the case, the risk of dying would be a fraction of the 1% it is generally believed to be, and infections would soon wane through “herd immunity” – achieved when more than two-thirds have acquired immunity to the virus.
“Because lockdown is such a drastic measure, I thought it was important to point out that the opposite extreme could match the data,” she says. “I felt I needed to get involved because I am really worried about the consequences of lockdown, particularly on underprivileged people, not only in this country but globally.”
Lockdown inflicts damage in more insidious ways than the virus, but the result can be the same, Gupta believes. Those in comfortable jobs who can work from home are largely insulated against the financial and mental stress of life in a pandemic. “My primary concern is that the lockdown is affecting a lot of people very adversely and it is causing deaths and will cause more deaths,” she says.
So far, the scientific data do not support Gupta’s best-case scenario. Blood tests performed by the Office of National Statistics (ONS) on nearly 1,000 people in England suggest that less than 10% of the population has been exposed to the virus. The figures are in line with other surveys, though regional differences exist. Last month, Matt Hancock, the health secretary, said that about 17% of Londoners might have had the virus, against nearer 5% in the rest of the country.
But Gupta believes the test data may substantially underestimate the number of people who have fought off the virus. She suspects that while physical distancing and the lockdown have helped suppress the epidemic, infections may have waned because of people’s natural resistance to the infection, for example through antibodies that fight related coronaviruses which cause common colds – but which would not necessarily show up in Covid-19 antibody tests.
“The epidemic has in many places displayed a pattern which suggests it’s been brought down by natural processes, which does not just include acquired immunity, but perhaps cross-protection from having other related viruses, and possibly some innate level of resistance to start with,” she says.
With best- and worst-case scenarios, reality often lies somewhere in between. But regardless of whether the pandemic has run its course or not, Gupta argues that a blanket lockdown is a drastic response to any infectious disease outbreak. It should have been more targeted from the start, she believes, and should become more targeted now.
“One possibility could have been to protect the vulnerable people and monitor the epidemic for longer and if we’d started to see deaths creep up in the younger population, among those who don’t obviously have co-morbidities, then lock down at that point, or lock down for a couple of weeks, which the economy can endure, and try and analyse the data globally to see what’s going on,” she says.
“Should we be lifting the lockdown faster? Yes. I don’t think the halfway house situation is helpful. It’s already underscoring the inequalities that exist and those are going to get worse and worse.” She favours shielding the vulnerable but releasing the rest, while keeping physical distancing and hand hygiene measures in place.
Speaking in a personal capacity, Mark Woolhouse, a professor of infectious disease epidemiology at Edinburgh University, who sits on the Sage modelling subgroup, says scientists have no doubt that releasing all population-wide physical distancing measures would spark a resurgence of infections and a second wave. But he agrees that a more nuanced approach is needed to control the epidemic.
In the UK, the over-75s are 10,000 times more likely to die from Covid-19 than the under-15s, he points out. “That is a massive, massive difference. When you see something like that as a public health scientist, you don’t think of a blanket lockdown. This disease is massively concentrated in the older age group. We need to concentrate efforts where they are needed most and where we really need attention is in the care homes.”
He added: “It is not clear to me that population-wide measures were ever actually the right way to go with this. I actively supported the lockdown specifically on the understanding that it was a temporary, time-limited emergency measure. I was not thinking of something that would drag on for months. I was expecting that we would develop a more nuanced strategy once we realised some groups were 10,000 times more at risk than others, that we would adjust our strategy accordingly. And that is only just starting to happen now. It’s not what I signed up for.”