A list of 16 sectors where fully vaccinated workers may be exempt from isolation if they are told to quarantine after coming into close contact with a positive Covid case has been released by the governement.

It comes as more than 600,000 people were told to self-isolate in the week up to 14 July, leaving some industries with staff shortages.

Transport and retail bosses warned of empty shelves and travel disruption due to the 'pingdemic', with many staff having to stay off work after being alerted by the NHS Test and Trace system.

Now, new guidance for England published last night, revealed that employees providing critical services would only be able to keep working and avoid self-isolation after being identified as a contact if they were named on a list kept updated by officials.

The exemptions – in 16 sectors including essential transport, food supply, emergency services and energy – will allow people identified as contacts by NHS Test and Trace or the app to carry on working if their failure to do so would have a “major detrimental impact” or risk national security.

The policy only applies to named workers who are fully vaccinated and it is not a “blanket exemption” for all employees in a sector – for instance, while railway signal operators on whom the network depends may be given an exemption, individual train drivers are unlikely to be.

The guidance is intended to operate until August 16, when a wider exemption from self-isolation will apply to fully vaccinated contacts.

Full list of sectors who may be exempt from Covid isolation:

• Border control
• Civil nuclear
• Clinical consumable supplies
• Digital infrastructure
• Emergency services
• Energy
• Essential chemicals
• Essential defence
• Essential transport
• Food production and supply
• Local government
• Medicines
• Medical devices
• Waste
• Water
• Veterinary medicines

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.

Nadra Ahmed speaks about care home staff and issues with the 'pingdemic'

In Folkestone, this resulted in a shortage of drivers, with a park and ride scheme being cancelled, and garden waste collections suspended.

Some products are also running low in shops, with Sainsbury's reassuring customers yesterday that shoppers will still be able to find what they need.

A Sainsbury’s spokesman said: “We are working hard to ensure customers can find what they need.

"While we might not always have the exact product a customer is looking for in every store, large quantities of products are being delivered to stores daily and our colleagues are focused on getting them onto the shelves as quickly as they can."

Nadra Ahmed, chair of the National Care Association, said it is a challenging time for social care with staff shortages.

She said: "Every single day we are consistently getting messages from providers saying that they're really worried about the staff situation.

"We're already understaffed as it is, we've got vacancies all across the country.

"We've got mandatory vaccinations looming over us, with two or three members of staff potentially in a service who might be leaving because of it and so they need to find a role elsewhere.

"And on top of that you've got this isolation alert which comes out, which puts somebody out of action for the period of time.

"I've heard of 30% of staff have been isolating."

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