The system – hailed as “world-beating” by health secretary Matt Hancock and others – should have been able to curb the spread when cases were originally low, Professor James Naismith said.
“That was certainly the theory and the promise of the track and trace system,” said the professor of structural biology at the University of Oxford.
“With numbers as low as they were and a reasonable amount of lockdown, if track and trace was ever going to work and make a difference it would be this time – but it doesn’t seem to have made a difference at all.”
“The simple answer is that it doesn’t work,” Prof Naismith said, adding: “The evidence is there for everyone to see.”
The warning came after the latest daily figures revealed another 3,383 confirmed Covid cases, with up to 75 per cent thought to be the Indian variant.
Blackburn with Darwen reported 584 cases in the seven days to May 26, the equivalent of 390.1 cases per 100,000 people and the highest seven-day rate for the area since the start of February.
The seven-day rate in Bolton stands at 386.7 cases per 100,000, which is down from 452.8 on May 21 and suggests that the surge in cases may have peaked.
Boris Johnson is under increasing pressure to slam the brakes on his plan to lift all Covid restrictions on 21 June, some scientists fearing a third wave of the pandemic is already under way.
The British Medical Association has warned the government not to “repeat past mistakes with a premature easing of measures that could “undermine our health service”.
And Dr Adrian Boyle, vice president of the Royal College of Emergency Medicine, warned of a “perfect storm of hospitals just not having enough capacity.”
Professor Adam Finn, from the Joint Committee on Vaccination and Immunisation, said: “There’s vulnerability across the country. The idea that somehow the job is done, is wrong.
“We’ve still got a lot of people out there who’ve neither had this virus… nor yet been immunized, and that’s why we’re in a vulnerable position right now.”
But Professor Sir Mark Walport, a former chief scientific adviser, said that more data was needed before the final decision could be made about the June 21 easing of restrictions.
“We need to substitute speculation for scientific data that’s the truth of the matter. As everyone has said in the last few days, the situation is very delicately balanced with some three sets of moving parts,” he said.
“Firstly we have got a new more transmissible variant, of that there is no doubt, though we don’t know exactly how much more transmissible.
“Secondly, there’s been a change in behaviour following the relaxation of measures on May 17, and the effects of that will just be starting to come through.
“And, thirdly, we’ve got a vaccination programme that is very successful, but with a lot of people that still need both their second dose of vaccine and vaccination from scratch.”