The Government's chief scientific advisor Sir Patrick Vallance said there is "room for improvement" in the NHS Test and Trace system as its performance reached yet another record low nationally.
Data from the Department for Health and Social care shows 1,667 people who tested positive for Covid-19 in Wolverhampton were transferred to the Test and Trace service between May 28 and October 14.
Contact tracers ask these patients to give details for anyone they were in close contact with in the 48 hours before their symptoms started.
In Wolverhampton this led to 3,651 close contacts being identified over the period – also referred to as "non-complex" cases, meaning they could be dealt with through a call centre or online.
But just 55.9 per cent were reached – down from 56.5 at the start of the scheme to September 23, 56.4 by September 30 and 56.2 by October 7.
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There were 1,377 people who tested positive in Dudley who were transferred to Test and Trace – with 3,484 close contacts identified over the period.
But just 61.7 per cent were reached – down from 65.2 per cent at the start of the scheme to September 30, and 62.8 per cent by October 7.
A total of 2,903 people who tested positive for coronavirus in Sandwell were transferred to the service between May 28 and October 14. It led to 6,560 close contacts being identified – but just 57.1 per cent were reached.
In Staffordshire, the data shows 4,110 positive cases were transferred to the service between May 28 and October 14 – with 9,083 close contacts identified. But only 65 per cent were reached – meaning 3,180 people were not contacted or did not respond.
And in Walsall there were 1,890 people who tested positive – with 3,981 close contacts identified. But just 62.3 per cent were reached – up slightly from the 62 per cent in the period to October 7.
Across England, 57.6 per cent of non-complex close contacts were reached and told to self-isolate by NHS Test and Trace in the latest week to October 14.
Including complex cases – those linked to settings such as hospitals, schools or prisons – the contact tracing rate was 59.6 per cent, the lowest percentage since test and trace began.
At a recent Downing Street press conference, Sir Patrick 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.”
In Wolverhampton, 365 new positive cases were transferred to test and trace in the latest week, NHS figures show. In Dudley it was 334, in Sandwell 526, in Walsall 463 and in Staffordshire 1,098.
Across England, around 97,000 cases were transferred – a figure that has increased sharply since the end of August.
Ian Hudspeth, chairman of the Local Government Association, said it is concerning that the test and trace system is "going backwards".
He added: “If we are to prevent this second wave from escalating further, we need the system to meet the recommended 80 per cent benchmark if it is to have any chance of success."
Data also shows that in the latest weekly period, just 15.1 per cent of people who were tested for Covid-19 nationally at a regional site, local site or mobile testing unit – a so-called in-person test – received their result within 24 hours.
This was down from 32.8 per cent in the previous week and is the lowest rate on record.
Prime Minister Boris Johnson said at the Number 10 press briefing that he shares people's "frustrations" over the turnaround times, admitting that the system needs to improve.
Saffron Cordery, deputy chief executive of NHS Providers, which represents trusts across England, said: "These figures provide yet more evidence that the test and trace system is falling short.
"The figures on turnaround times are particularly disturbing."