The NHS' flagship test and trace system tracked down less than half of positive patients' 'contacts' in the first three days of its launch, figures suggested last night.
A leaked report claimed that virus sufferers had provided details of 4,634 people they might have infected, of whom just 1,749 were texted or emailed.
The Department of Health pointed out that the figures were four days out of date, insisting the majority of contacts had since been alerted. But the document obtained by Channel 4 News comes amid concerns that many of those employed by the scheme have had nothing to do.
The NHS' flagship test and trace system tracked down less than half of positive patients' 'contacts' in the first three days of its launch, figures suggested last night (File image of NHS tracing app)
Test and trace was launched by Health Secretary Matt Hancock last Thursday. He hailed it as a 'new way of life' that would enable the country to come out of lockdown.
Hancock under fire over his figures
Matt Hancock has become embroiled in a public row with the country's top statistician over testing figures.
Sir David Norgrove accused the Government of misleading the public with its daily testing figures, saying they are 'still far from complete and comprehensible'.
Matt Hancock has become embroiled in a public row with the country's top statistician over testing figures
It is the second time the UK Statistics Authority chairman has hit out at the way Covid-19 tests are being presented. Sir David said it was 'not surprising' the data had been 'widely criticised and often mistrusted'. Health Secretary Mr Hancock responded by saying he would publish details of how the 200,000 tests would be counted.
The Government has hit targets to have the capacity for 200,000 tests by the end of May. But in a letter to No 10, Sir David said: 'The aim seems to be to show the largest possible number of tests, even at the expense of understanding.'
A Department of Health spokesman said: 'Our approach throughout has been to increase transparency.'
Anyone with virus symptoms is urged to order a test and if the results are positive, they are asked for the mobile phone numbers or email addresses of their recent contacts.
This includes people with whom they had spent at least 15 minutes at a distance of less than two metres – in the two days before the symptoms began and five days after.
These contacts are then texted or emailed and asked to self-isolate for up to 14 days.
Yesterday the Government launched a major information campaign on the scheme with TV, radio and online adverts.
And on Monday, Mr Hancock claimed the system was 'working well', although he repeatedly refused to provide figures for the number of people who had been traced.
But Baroness Harding, who is leading the programme, reportedly told MPs last week she did not expect the system to be properly up and running until the end of this month due to likely teething problems.
The Government is hoping to publish up-to-date figures this week, then weekly updates thereafter, once it has confidence in the data.
Department of Health officials stressed that many patients with the virus were not suitable for contact tracing because they were in hospitals or care homes.
Up to 25,000 contact tracers have been hired alongside 3,000 clinical case workers. They earn between £10 and £27 an hour, depending on their expertise.
But three contact tracers told the Mail earlier this week that they had not made a single call. Another claimed she had spent much of her time reupholstering a chair because she had so little to do.
A Department of Health spokesman said: 'These figures are outdated and fail to reflect the huge amount of work already under way, with thousands of people already contacted in just a matter of days and their contacts successfully traced.
'We are working with the UK Statistics Authority to finalise the most useful information to publish on its performance and will be providing weekly updates shortly.'