Scientific advisers to the government believe that an effective test, track and trace system must be in place before schools reopen to more pupils.
The Scientific Advisory Group for Emergencies (Sage) has advised the government that, in order to enter the next phase of the lockdown plan - in which schools would be partially opened - a test, track and isolate system should be established.
Sage believes this system does not need to be 100 per cent effective from day one, but it should be in place by the time changes are made.
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The scientific advisers to the government believe that it is safest to open schools when the incidence level is low; the R is below 1; systems are in place to be able to measure the effect; and systems are in place to be able to detect outbreaks and deal with them quickly.
Sage says the R value remains between 0.7 and 1.
Public health experts have warned that opening schools to more pupils before the contact tracing system is in operation would risk a further spike in the number of cases of Covid-19.
The prime minister has said he has the “great confidence” that there will be a “world-beating” test, track and trace system in place by the time schools reopen to more pupils on 1 June.
A Department for Education spokesperson said: “The evidence published today shows we looked at a range of options in drawing up this phased approach to reopening schools, which is in line with the government’s overall ‘roadmap’.
“As in other countries across Europe, the first phases of the wider opening of schools will prioritise younger children.
“Advice from Sage shows there is a lower overall risk from opening schools and nurseries to younger children, and that they are less likely to become unwell if infected with coronavirus compared to adults.
“This cautious, phased approach for allowing a limited number of pupils back into classrooms has been, and will continue to be, informed by the best possible scientific and medical advice.”
