NHS Test and Trace is failing to reach contacts of positive coronavirus cases because people won’t answer their phones to unknown numbers, an expert has warned.
Dr Susan Hopkins, an epidemiologist and medical adviser for the test and trace sevice, said difficulties also arise from others not leaving their contact details.
She told BBC Breakfast on Monday: “Firstly, the teams make every effort to call individuals.
“We do need to get people’s contact details from the primary case.
“Usually, about one in five individuals, there’s no contact details given. So we struggle to find that individual and then cases through the system.
“People don’t answer their phones, people don’t want to get a contact from an unknown number.
“And that’s part of the reason why there’s increasing local contact tracing, working with directors of public health and local councils, so that their local system can find some of these individuals that the national system cannot.”
Test and trace has been widely criticised for failing to reach sufficient numbers of close contacts of people who have tested positive for COVID-19 and persuading them to isolate.
In May, Boris Johnson promised a “world-beating” contact tracing scheme.
But the most recent data shows that two in five contacts in England are still not being reached.
Some 60.3% of close contacts of people who tested positive were reached in the week ending 21 October, far short of the 80% needed in order for the system to be effective, according to scientists advising the government.
Experts on the government’s Scientific Advisory Group for Emergencies (Sage) warned in September the £12bn scheme was having only a “marginal impact” on curbing infections.
Just 22.6% of people who were tested for COVID-19 in England in the week ending 21 October at a regional site, local site or mobile testing unit – a so-called “in-person” test – received their result within 24 hours.
The prime minister had pledged that, by the end of June, the results of all in-person tests would be back within 24 hours.
The Sunday Times reported at the weekend that thousands of people were not contacted by the NHS Test and Trace app because of a software glitch.
The newspaper quoted a government source as saying “shockingly low” numbers of people had been alerted through the app since it launched on 24 September.
It comes after the prime minister announced that England will return to lockdown from Thursday, with pubs, restaurants, gyms and non-essential shops forced to close.
On Sunday, Labour leader Sir Keir Starmer said the government needs to fix test and trace in order to come out of the lockdown.
Watch: Sir Keir Starmer says test and trace needs to be fixed
He said: “The government has to keep its side of the bargain here, because if they don’t use this time to fix Test, Trace and Isolate, then I think December 2 will be a review date not an end date.
“Because for months and months and months they’ve promised a world-beating Test, Trace and Isolate system which is vital… it’s been busted for months.
“Use the time to fix it, because otherwise we’re going to be back in this cycle for months and months and months.”
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