The Prime Minister has admitted that the NHS Test and Trace system needs to improve, after it was revealed that just one in seven people having a test at a centre is getting their result back in 24 hours.
Boris Johnson said he shares people’s “frustrations” with the system and said there needed to be faster turnaround times.
The new weekly data from the programme shows 15.1% of people who were tested for Covid-19 in England in the week ending October 14 at a regional site, local site or mobile testing unit – a so-called in-person test – received their result within 24 hours.
This is down from 32.8% in the previous week and is the lowest weekly percentage since Test and Trace began.
Watch: Boris Johnson admits 'frustrations' over Test and Trace
The Prime Minister told the Downing Street press conference on Thursday: “I share people’s frustrations and I understand totally why we do need to see faster turnaround times and we need to improve it.
“We need to make sure that people who do get a positive test self-isolate – that’s absolutely crucial if this thing is going to work in the way that it can.”
The Government’s chief scientific adviser Sir Patrick Vallance said it is “very clear” that there is “room for improvement”.
He told the press briefing: “It’s undoubtedly the case that test, trace and isolation becomes much more difficult to have an impact once numbers are high, it’s much more effective when numbers are low.”
Sir Patrick said it is “really important to concentrate on numbers of contacts, isolation as quickly as you can and getting things back as quickly as you can – ideally you get the whole process done within 48 hours”.
He added: “It’s very clear there’s room for improvement on all that and therefore that could be diminishing the effectiveness of this.”
It is “very difficult” to remove from circulation everyone who is infectious at the moment due to the high levels of cases, Sir Patrick said.
The figures from the NHS Test and Trace system show a drop to 59.6% in the proportion of close contacts of people who tested positive who were reached.
This is the lowest weekly percentage since Test and Trace began and is down from 63% in the previous week.
For cases handled by local health protection teams, 94.8% of contacts were reached and asked to self-isolate in the week to October 14.
But for cases handled either online or by call centres, this figure was 57.6%.
The data also shows the positivity rate – the proportion of all tests returning a positive result – has climbed to 7.1% for the week, the highest since Test and Trace began.
According to criteria published by the World Health Organisation, a positivity rate of less than 5% is one indicator that the epidemic is under control in a country.
A total of 101,494 people tested positive for Covid-19 in England at least once in the week to October 14 – a rise of 12% in positive cases on the previous week.
The latest data shows that of 96,521 people transferred to the system, 80.7% were reached and asked to provide details of recent close contacts.
This is up slightly on 79.9% in the previous week.
Labour’s Justin Madders said it was time for ministers to admit that the private companies being paid millions of pounds to help run the system “aren’t up to the job”.
Shadow health minister Mr Madders said: “To have over 40% of people not even being contacted by the test and trace system is an interstellar-sized black hole in the Government’s plan to reduce transmission.
“How much longer are we expected to put up with this dangerous failure before ministers admit that the likes of Serco just aren’t up to the job?
“The need for a circuit-break is absolutely critical now and that time should be used to fix Test and Trace once and for all.”
Interim executive chair of the National Institute for Health Protection, Baroness Dido Harding, said reducing turnaround times is “our absolute priority to make sure we are reaching people as soon as possible”.
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