NHS staff are quietly deleting the Covid tracing app amid calls from hospital leaders for doctors and nurses to be exempted from self-isolation rules before August.
It came as business leaders warned the app was causing huge levels of staff absences, sparking fears that some companies will be unable to cope after "Freedom Day".
Healthcare workers are advised to "pause" contact tracing on the app while working in clinical settings, with personal protective equipment worn when required. But NHS managers said some staff were privately leaving the app off at all times or deleting it because they feared being forced to self-isolate.
One said: "I had Covid in the first wave, I’ve been double jabbed – I can’t keep isolating every time the app pings. I switched it off ages ago, and I think a lot of staff who are double vaccinated have done the same."
A senior doctor said: "I have already had to stay at home several times recently, when the children were sent home from school to isolate. I can’t have the app on top of that, so I deleted it."
Chris Hopson, the chief executive of NHS Providers, which represents hospitals, said: "Trust leaders are already asking whether, if double-vaccinated members of the public won’t be required to self-isolate after August 16, this date can be brought forward for NHS staff, who were of the first groups to be vaccinated."
He said there was a "major risk" that "even more NHS staff would have to self-isolate as community infections rates spiked.
Stephen Reicher, a member of the Government’s scientific pandemic insights group on behaviours (SPI-B), said the "real danger" was that people could start to ignore requests to self-isolate if they believed the Covid crisis was over.
"People are not going to put up with these things if they think it’s a waste of time, it’s not necessary and there isn’t a risk, and all the signalling that’s going on, talking about ‘freedom’ – the implication is it’s all over," he added.
On Wednesday, Jonathan Ashworth, the shadow health secretary, raised fears of "huge swathes" of public services unable to cope in the coming weeks because of the numbers self-isolating.
Mr Ashworth said changes planned for August 16 should be brought forward, with people instead given daily lateral flow tests and PCR tests when needed.
He told BBC Radio 4’s World at One programme: "Otherwise you are going to find huge swathes of public services unable to cope because their workforce will be isolating."
Richard Walker, the Iceland supermarket boss, said the opening up from July 19, almost a month before self-isolation rules are relaxed for the double-jabbed, would result in a "s—show" for business.
"Our Covid-related absences are growing exponentially," he said. "Within a week or two, they’ll be the highest ever. "Covid rules end July 19. Self-isolation rules were not eased until August 16. This will be a s—show for business."
How many people have been vaccinated?
Flavio Toxvaerd, an economist specialising in economic epidemiology at the University of Cambridge, said: "I have a very strong belief that people will be either deleting or ignoring the app moving forward.
"People would have followed the rules to the extent that they thought they were reasonable and necessary, and if all indications from policy announcements is that really we are just on the last stages before opening up completely then there is much less a sense of urgency."
On Wednesday, Sir Keir Starmer, the Labour leader, said there were already "too many stories" of people deleting the app.
There were now growing calls for ministers to urgently introduce a test and release system for employees and NHS staff.
However, Kwasi Kwarteng, the Business Secretary, said that while August 16 was not a "perfect solution" it was unlikely that date would be brought forward.
A senior figure in the hospitality industry raised fears that pubs and restaurants struggling to stay open due to staff shortages could start "tacitly" asking employees to delete the app, which works by detecting if someone has been in close contact with a person who later tests positive. It then advises people to self-isolate but does not have the legal force of manual contact tracing.
"I suspect people will tacitly say ‘delete the app’. People will be telling employees to take it off their phones," the source added.
Fears are mounting that, if Covid cases hit 100,000 a day, millions of people could be forced to self-isolate each week by August, exacerbating problems with staff shortages.
Last week, Dr Ben Lovell, an associate professor of medical education and a consultant in acute internal medicine at UCL Hospitals, said his hospital was "desperately, desperately desperately understaffed due to the NHS Covid app telling Covid-negative, asymptomatic, double-vaxxed doctors to go into isolation for up to 10 days at a time".
Professor Christophe Fraser, of Oxford University’s Nuffield Department of Medicine, which advises Test and Trace, said usage of the app is at an "all-time high".
"About 50 per cent of overall test results nationally go through the app," he told Times Radio. "The team monitors the usage of the app, and at this point in time the usage of the app is at an all-time high."
On Wednesday, Boris Johnson was asked about suggestions that the delays to easing the self-isolation rules could mean an extra five million people forced to quarantine at home. He said: "All these decisions are a balance of risk. This is a highly contagious disease. We have to do what we can to stop its spread. We have been looking at all the data and trying to strike the right balance."