A record number of people were told to isolate by the NHS Covid-19 app when more than 600,000 alerts were sent to users in a week, figures suggested, as retailers warned of disruption.

Former health secretary Jeremy Hunt said the Government risks “losing social consent” for isolation if it does not immediately bring forward the relaxation of quarantine rules for the fully vaccinated.

Business Secretary Kwasi Kwarteng told shoppers not to panic in the face of supermarket shortages and attempted to ease concerns over the “pingdemic” as Covid-19 cases soar.

He said a “very narrow” list of sectors whose workers will be exempt from isolation rules would be published later on Thursday, but Downing Street later suggested it would instead be “examples of the sectors where exemptions could apply”.

Warnings of staffing shortages mounted as NHS figures showed 618,903 alerts were sent to users of the coronavirus app in England and Wales in the week to July 14, telling them they had been in close contact with someone who had tested positive for coronavirus.

Mr Hunt, who chairs the Health and Social Care Committee, urged ministers to bring forward the scheduled end of isolation for all fully vaccinated contacts who test negative from August 16.

The Conservative MP warned in the Commons that without scrapping that requirement and replacing it with testing “we risk losing social consent for this very, very important weapon against the virus”.

Confederation of British Industry director general Tony Danker echoed the call, saying the Government must end its “awkward compromise”.

“The current approach to self-isolation is closing down the economy rather than opening it up,” Mr Danker said.

“Businesses have exhausted their contingency plans and are at risk of grinding to a halt in the next few weeks.”

In the face of mounting pressure, Mr Kwarteng told BBC Breakfast the “list” of sectors where exemptions could apply would be “very narrow, simply because we don’t want to get into a huge debate about who is exempt”.

Cumulative UK Covid-19 vaccinations
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He said he would not “pre-empt” the details when asked if the food industry would be on it, amid pleas from bosses to prevent major staff shortages.

But businesses expecting comprehensive details look set to be disappointed as a No 10 spokesman characterised the publication as “guidance” that “will set out in more detail how the process will work, how to apply and examples of the sectors where exemptions could apply”.

Iceland’s managing director, Richard Walker, said the supermarket was having to hire 2,000 temporary workers to prepare for “the exponential rise in pinging”.

“The dramatic pictures that you might have seen in the media are isolated incidents and not widespread,” he told BBC Radio 4’s Today programme.

Daily confirmed cases of Covid-19 in the UK
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“But the people who should be panicking are the Government, and I believe that, you know, the sooner they clear up this mess, and get retail workers and HGV drivers on to the key worker list, the better.”

Mr Kwarteng responded: “He was right to say shoppers shouldn’t be panicking. I don’t quite know what he meant that the Government should be panicking, I’m not panicking.”

The British Retail Consortium (BRC) urged ministers to “act fast” to issue exemptions from isolation, with the wider relaxation not scheduled until a month after most coronavirus laws ended in England.

That date “feels a long time away”, BRC chief executive Helen Dickinson said, as she warned stores are closing, hours are being reduced and consumers are facing reduced choice.

“I think what the most important thing for Government to do is to recognise that the current situation is untenable,” she told BBC Breakfast.

Meanwhile, officials announced a further 39,906 lab-confirmed Covid-19 cases in the UK and that an additional 84 people had died within 28 days of testing positive for Covid-19.

Covid-19 vaccine doses in the UK
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A lorry driver shortage was putting increased pressure on the country’s grocery supply chain and empty shelves were witnessed in some supermarkets across the country.

Mr Kwarteng had to tell businesses to “stick to the rules” after a food distribution company struggling with staff shortages advised workers who are pinged by the NHS app to take tests and continue working, in breach of the Government advice.

Bidfood chief executive Andrew Selley defended his approach for delivery drivers to continue working if they have negative results as “appropriate and safe” for the “critical workers”.

“If they are pinged we ask them to take a PCR test, if that’s positive then clearly they’ll isolate but if it’s negative we ask them to come back to work and we have a process of doing lateral flow tests daily away from their workplace and if that’s negative they can proceed with their work,” he told Today.

Professor Ravi Gupta, a scientist advising the Government as part of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), described it as a “mixed bag of measures which are creating confusion and havoc”.

“I think it is a little bit difficult to justify people doing self-isolation when in fact we have held huge sporting events with large amounts of transmission that have probably gone undetected,” he told Sky News.

Dr Tom Dolphin, a spokesman for the British Medical Association and a consultant anaesthetist in central London, said it was “very unfortunate” that people are deleting the app to avoid pings.

“The reason there’s a pingdemic is because there’s a pandemic. People are being infected and testing positive in huge numbers, and blaming the app for that is like blaming the fire alarm for going off when there’s a fire, he told Sky.

Mick Lynch, general secretary of the Rail, Maritime and Transport union, told the PA news agency: “RMT will give consideration to proposals from companies on critical workers exemptions but nobody should be under any illusions about how fraught with difficulty and potential danger any system will be to operate in practice.

“All workers have the right to work in a safe system and environment that is properly risk assessed with proper controls. Our members in workplaces where pinged staff are exempted will clearly be subject to an elevated level of risk as the alerted staff would normally be isolating for very good reasons.

“There is a real danger of a headlong rush into these new measures driven by this inept government which could make a bad situation even worse.

“Before any implementation, employers need to produce proper risk assessments agreed with the union that consider and control the enhanced risks to all staff and ensure that the principle objective of workplace safety is maintained and fully enforced.”