Local teams continue to be more successful than call centre workers when it comes to reaching the close contacts of people who tested positive for coronavirus.
New figures from the Department of Health and Social Care show local health protection teams traced 98% of contacts, while for online or call centre teams that number was 56.1%.
When people are reached, they are asked to self-isolate for two weeks from the day they were last in contact with the infected person.
There has been a consistent gap between local teams and call centres/online since the NHS Test and Trace system for coronavirus launched in England in late May.
In the first week, the local figure was 99.7% and the call centre/online statistic was 52.5%.
Experts have warned the scheme, which Prime Minister Boris Johnson previously promised would be “world beating”, must quickly improve to cope with the expected pressures when all pupils go back to school in September and as winter approaches.
Mr Johnson repeated this claim on Thursday, saying: “If you look at what we are doing, actually I think it certainly is – it certainly does fit that description of ‘world-beating’.
“I think I’m right in saying that we are now testing more – per head of population – than virtually any other country in Europe, certainly, in America they are testing a huge number of people.”
He said the test and trace system was “absolutely crucial” for the government’s coronavirus strategy.
“If you look at what we are doing with some of the local social distancing measures that we are bringing back in, that’s entirely driven by our ability to detect cases through local test and trace, working with our local authorities and taking the right local measures,” the PM said.
Some councils have launched local contact-tracing operations to supplement the national system.
Calderdale Council, which covers Halifax and surrounding areas, is the second authority to make the move after Blackburn with Darwen said it was setting up a locally focused system to utilise community knowledge because the government’s system was not fast enough.
But officials insist the national Test and Trace programme is not at odds with local systems, and is working in partnership with local authorities and their health protection teams.
National figures show 72.4% of close contacts were reached in the week ending 29 July, down from 76.2% in the previous week, and also a fall compared with the 90.7% reached in the first week of Test and Trace (week ending 3 June).
Since the system launched, 199,524 close contacts of people who tested positive for COVID-19 have been reached.
This represents 82.2% out of a total of 242,749 people identified as close contacts. The other 43,225 people (17.8%) were identified but not reached.
Meanwhile, Scotland has announced 67 new coronavirus cases – the highest daily rise in over two months. More than half (39) were in the Grampian area.
Some 25 of the new infections were in Aberdeen where there has been an outbreak in the city, with lockdown restrictions reintroduced, as bars, cafes and restaurants were ordered to close.
A five-mile travel rule has been put in place and residents are being told not to enter each other’s houses.
Some 79 confirmed cases have now been identified in Aberdeen and a further 30 are under investigation.
Across the UK, latest government figures show 65 more people have died in hospitals, care homes and the wider community in a 24-hour period up to 5pm on Tuesday, after testing positive for coronavirus. This takes the total to 46,364.
The government also said in the 24 hours up to 9am on Wednesday, there had been 892 further laboratory-confirmed cases.
Overall, a total of 307,184 cases have been confirmed.