The Test and Trace programme will need to be scaled up for schools to be able to reopen, experts warn.An effect system, in which people isolate when they test positive for Covid-19, will be needed to avoid a second wave later this year.The study comes as Australian research found there were 'low' levels of coronavirus transmission in schools and nurseries.And it comes after suggestions that pubs may need to be shut in order to allow schools to reopen while keeping the spread of Covid-19 down.The