Boris Johnson’s test-and-trace service faces fresh criticism after it reported its worst ever figures for tracking down “close contacts” of people with Covid.

The controversial system hit a new low with just 62.6% of cases in England being reached and told to self-isolate to stop the spread of the virus.

The figure is the worst since the so-called NHS Test and Trace was launched in May, and down on the previous week’s 68.8%, itself a record low at the time.

It means that nearly a third of all people who have been in contact with someone testing positive for the virus have not been reached – and not told to home quarantine for 14 days.

Government scientific experts have advised that the whole system can only work effectively if at least 80% of “close contacts” are actually tracked down and self-isolate

Close contacts are defined as those who have spent more than 15 minutes within two metres of a positive Covid case.

Latest figures for the week between October 1 and October 7 starkly underlined the continuing surge in coronavirus cases across the country, with 89,874 people testing positive for the first time – a 64% increase compared to the previous week.

The so-called NHS Test and Trace system, which is headed by Tory peer and former TalkTalk phone giant boss Dido Harding, has been dogged by criticism since it began earlier this year, with many attacking its use of private firms like Serco and Deloitte.

Although it has managed to dramatically increase testing capacity from 2,000 a day to around 300,000 a day, its performance on getting tests to those who need them has remained under fire.

Shadow health minister Justin Madders told HuffPost UK: “It is absolutely staggering that week upon week the performance of test and trace keeps getting worse and worse.

“Surely Ministers must see that the system is falling apart and what was supposed to be world beating is in fact now one of the biggest obstacles to us getting on top of the virus?

“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.”

Even on the government’s tweaked version of its contact rate target – defining it as for cases where communication details were available –  just 76.9% were reached and asked to self-isolate. Again this is below the crucial 80% figure needed to stem the spread of the virus.

There was slightly better news for ministers with a small rise in the proportion of people with Covid who were reached by the service, up to 76.8% from 74.9% in the previous week.

Testing turnaround times also showed a small improvement, with 32.6% of people who had an “in-person test” – at a regional site, local site or mobile testing unit – receiving their result within 24 hours.

This is up from 27.4% in the previous week, but still a long way short of the 100% that Boris Johnson promised earlier this year would happen by June. The median distance needed to travel to a test also fell.

For all testing routes, including home tests and satellite centres used for care homes, just 14.8% got results within 24 hours, up on the 12.8% in the previous week. 

Testing capacity, which is around 300,000 a day but is meant to hit 500,000 a day be the end of the month, also improved.

Across all “pillars”, it stood at 3,013,986 tests, a 5% increase compared to the previous week. For just “swab testing” – a more relevant measure for test and trace – there were 2,166,286 tests, a 30% increase since the start of
September.

Health secretary Matt Hancock told MPs: “This week’s NHS Test and Trace statistics show that testing capacity is up, testing turnaround times are down, and the distance travelled for tests is down too.

“And, thanks to this capacity and this analysis, we’ve been able to take a more targeted approach, keeping a close eye on the situation in local areas, bearing down hard through restrictions on a local level where they’re necessary.”

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