One third of people who tested positive for coronavirus could not be reached by the NHS Test and Trace programme in its first week of operation or failed to provide details of their contacts, data shows.
Some 8,117 people who tested positive for Covid-19 in England had their case transferred to the NHS Test and Trace contact tracing system, of whom 5,407 (67%) were reached, while 2,710 (33%) were not reached.
Baroness Harding, the head of the programme, admitted it was not yet at the “gold standard” but said it was now a “functioning service”.
Overall, 31,794 contacts were identified and, of these, 26,985 were reached and advised to self-isolate – 85% of the total number of contacts.
Of the 15%, some were not reached, others said they were already taking action independently of the system and some simply refused to comply.
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Baroness Harding admitted improvements were needed but said the system was “fit for purpose”.
“We are not at the gold standard yet that we want to be, of isolating all contacts within 48 hours of someone requesting a test,” she said.
“But you can absolutely see the path of how we are going to get there.”
Baroness Harding said the system had been “stood up in extraordinary time” and would get better through the summer.
The figures, from the Department of Health and Social Care, cover the period May 28 to June 3.
Baroness Harding said she was unable to give a date for the launch of the app which will form part of the test and trace programme she leads.
The app “is the cherry on the cake, it’s not the cake itself and what you are seeing today is the first baking of the cake is going reasonably well”, she added.
The programme said the number of people reached includes those who provided details about recent contacts or whose cases have been investigated as part of an outbreak.
The number that were not reached includes those where contact details were unavailable or incorrect, or where there has been no response to text, email and call reminders.
It also includes people who the service has been able to contact but who have not provided information about contacts.
This also includes people whose cases are currently being managed as part of active outbreak investigations.
Of those people who were reached and asked to provide information about their contacts, just over three-quarters (79%) were contacted within 24 hours of their case being transferred to the Test and Trace system.
Some 14% were contacted between 24 and 48 hours, 3% between 48 and 72 hours, and 4% were contacted after 72 hours.