Nearly four in 10 close contacts of people with coronavirus are still not being reached by the struggling test and trace regime in Swindon, figures suggest.

Shadow health minister Justin Madders said the heavily-criticised NHS Test and Trace system is “falling apart”, as he echoed calls for a circuit breaker lockdown amid another surge in positive cases.

Data from the Department for Health and Social care shows 861 people who tested positive for Covid-19 in Swindon were transferred to the Test and Trace service between May 28 and October 7.

The service asks these patients to give details for anyone they were in close contact with in the 48 hours before their symptoms started.

In Swindon, 2,381 close contacts were identified – also referred to as “non-complex” cases, meaning they could be dealt with through a call centre or online.

But just 62.2% of those were reached by contact tracers over the period, meaning 900 people were not contacted or did not respond.

However, that was slightly up from the 60.5% reached in the period to September 30.

Across England, 57.6% of non-complex close contacts were reached and told to self-isolate by NHS Test and Trace in the latest week to October 7.

Including complex cases – those linked to settings such as hospitals, schools or prisons – the contact tracing rate was 62.6%, the lowest percentage since test and trace began.

Mr Madders said: “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.”

In Swindon, 75 new cases were transferred to test and trace in the latest week, NHS figures show.

Across England, around 88,000 positive cases were transferred – a figure that has increased sharply since the end of August. It included roughly 11,000 cases that were delayed due to technical errors at Public Health England.

Health Secretary Matt Hancock defended the test and trace system, telling MPs that it has allowed for a “detailed picture” of where and how the virus is spreading.

“This week’s statistics show the testing capacity is up, testing turnaround times are down, and the distance travelled for tests is down too,” he added.

But Saffron Cordery, deputy chief executive of NHS Providers, which represents trust leaders, said: “It’s deeply unfortunate that at this point with infections rising, admissions increasing and winter looming, there’s still clearly a long way to go until our test and trace system is fit for purpose.”