The UK must improve its Covid-19 tracing programme amid fears that a second wave of the virus could be twice as bad as the first, researchers said. A study found that reopening British schools as planned in September must be accompanied by an effective trace, track and isolate programme to keep infections down. The UK has suffered more than 46,000 deaths during the pandemic, putting it below only the US, Brazil and Mexico, according to a tally by Johns Hopkins University. Researchers from University College London and the London School of Hygiene & Tropical Medicine found that three quarters of people with the disease would need to be diagnosed and isolated and two thirds of their contacts traced if schools returned full-time in September. If the level of contact tracing fell below that threshold in the UK while schools reopened full-time and control measures were eased, a secondary wave of Covid-19 would peak in December, according to a report in <em>The Lancet Child & Adolescent Health </em>journal<em>. </em> The authors issued a warning that a secondary wave of infections could be two to 2.3 times the size of the original outbreak. Dr Jasmina Panovska-Griffiths, who led the study, said: “Our modelling suggests that with a highly effective test and trace strategy in place across the UK, it is possible for schools to reopen safely in September. “However, without sufficient coverage of a test-trace-isolate strategy the UK risks a serious second epidemic peak either in December or February.” The study was published as British former prime minister Tony Blair’s think tank called for more testing and transparency to limit the impact of the government’s quarantine policy on international arrivals. The think tank said the measures, which require international passengers arriving from certain countries to quarantine for 14 days, risk further grinding the travel industry to a halt. ___________