UK 18 May 2020 Why Covid-19 testing and tracing is the most urgent challenge for the UK The only certain route out of lockdown is to reduce the level of community transmission. Getty Images Paramedics return to their ambulance at Aintree University Hospital in Liverpool on 14 May 2020. Sign UpGet the New Statesman's Morning Call email. Sign-up Will there be a Covid-19 vaccine by the end of the year? We don’t know. What are the long-term health effects of having the novel coronavirus on those who get it? We don't know. Is long-term immunity from the disease even possible? We don’t know. Could the novel coronavirus vanish unexpectedly? We don't know. Are schools significant vectors of infection? We don’t know. What we do know is that the impact of school closures is uneven – it falls particularly heavily on the disadvantaged. So you can argue the case on schools either way – should you wait for more information or rush to reopen them as soon as is practicable? And what does as soon as is practicable mean in any case? What we know is that the only certain way out of lockdown is to be able to reduce the rate of community transmission and to test, trace and isolate new cases – and getting capacity right for that challenge is more important or urgent than practically everything else. › How mental health services can support every child Stephen Bush is political editor of the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics. Subscribe To stay on top of global affairs and enjoy even more international coverage subscribe for just £1 per month!