Lockdown could last until summer, No 10 warns as experts warn relaxation of rules could trigger new Covid wave

Sign up for our free Health Check email to receive exclusive analysis on the week in health Get our free Health Check email Get our free Health Check email SIGN UP I would like to be emailed about offers, events and updates from The Independent. “There’s no possibility up to phase one that we’ve reached the herd immunity threshold and … there are still vulnerable people in the population who may get infected.” In the scenario where there is 90 per cent vaccine uptake among the JCVI’s vulnerable groups, 1 million at-risk people will still be susceptible to Covid-19. “If we do it too quickly we tend to have large-scale outbreaks – bigger than what we’re seeing at the moment – and so the key is slow relaxation and high levels of infection blocking from the vaccine.” Dr Anne Cori, a lecturer in infectious disease modelling at Imperial College London, stressed that the extent to which the government can ease lockdown measures “really depends on the proportion of the population that is protected”, the speed of the rollout, the effectiveness of the vaccine and uptake. Prof Woolhouse said “it depends on a number of things including coverage and key unknowns about the vaccine performance”, such as the jabs’ ability to prevent transmission and the duration of protection they offer, along with natural immunity acquired via infection. “We’ll look at how we’re doing but I think what we’re seeing in the ONS data, in the React survey, we’re seeing the contagiousness of the new variant that we saw arrive just before Christmas – there’s no doubt it does spread very fast indeed.” The authors of the latest React study from Imperial College London have meanwhile said that Covid-19 infections may have risen during the first week of the national lockdown, raising concern over the effectiveness of the current restrictions.