Covid-19: Why are scientists concerned about Test and Trace?

The Department of Health and Social Care (DHSC) has said that the system is working but it has been criticised for not reaching enough people who have tested positive or their close contacts. So what is the Test and Trace service and why are scientists concerned about it? The authors of a new modelling study said that without appropriate levels of testing and contact tracing, reopening of schools together with gradual relaxing of the lockdown measures are “likely to induce a second wave that would peak in December 2020 if schools open full-time in September”. The study, published in The Lancet Child And Adolescent Health, warned that in a worst-case scenario a second wave could be 2.3 times higher than the first. But its authors said that “with increased levels of testing… and effective contact tracing and isolation, an epidemic rebound might be prevented”.