More than 100,000 people in England have been asked to self-isolate by contact tracers in the past three weeks to contain coronavirus, data shows.
The individuals have all had close contact with people who have tested positive for the virus.
They have been told to stay at home by the NHS Test and Trace service, which launched at the end of May.
The service has tried to trace the contacts of more than 20,000 people who have tested positive for Covid-19.
One in four did not engage with the service.
Those that did provided details for nearly 130,000 contacts.
Nearly 114,000 of them – about nine in 10 – have been reached by the service over its first three weeks and asked to self-isolate at home.
The service has once again not been able to provide details for how quickly people are being contacted following a positive result.
Government advisers believe contacts need to be found within 48 hours for the service to be most effective.
Public ‘must play its part’
Prof Keith Neal, an expert in infectious diseases from the University of Nottingham, said the biggest issue lay with the attitude of the public.
He said the numbers coming forward for testing was thought to be lower than the actual number who are infected, while the fact that one in four people who test positive do not engage with the system was “worryng.”
“These can only be sorted by members of the public as they require individuals to take the appropriate actions to reduce spread.”
It comes as the NHS Test and Trace programme has started trialling walk-in testing centres. The pilots are being held in London, Newcastle, Rochdale and Slough.
They involve buildings as well as open-air locations, including a basketball court.
Currently, testing is available at hospitals, mobile testing units, regional drive-through centres, and via a postal service.
Scotland, Northern Ireland and Wales run their own tracing services.
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