Factories across the country are on the verge of shutting down due to isolation warnings from the test and trace app, the UK’s manufacturing union Unite has claimed.

The union says it has been warned by a number of companies, particularly in the automotive sector, that swathes of staff are being advised to self-isolate by the NHS app, causing worker shortages and disruption to production.

This follows reports that more than 700 workers at Nissan’s Sunderland factory were forced to stay off work and isolate, leading to a number of shifts being cancelled entirely.

One major engine supplier told Unite that delays to orders are so severe that work may be permanently moved to China, the union said in a statement.

“No one is advocating for coronavirus controls to go out the window and Unite’s number one priority remains the health and safety of our members,” said Steve Turner, Unite assistant general secretary.

“But the reports Unite is receiving from our members and their employers are extremely worrying,” he said. “It is not an exaggeration to say factories are on the verge of shutting and that at some sites hundreds of staff are off work.”

Mr Turner warned that people would simply start deleting the app if a solution wasn’t found soon.

The union said it had been made aware of a trial being held at a UK automaker to reduce the amount of unnecessary self-isolations, which it said industry leaders were keen to replicate to prevent UK manufacturing from being crippled.

“It is clear that something has to be done in time for July 19, or else people will simply start deleting the app en masse to avoid isolation notices,” Mr Turner said. “There will be public health consequences if test and trace becomes seen as a nuisance rather than an infection control measure.”

Earlier this week, passengers faced long queues at Heathrow after security staff were told to self-isolate.

A spokeswoman said: “Earlier today we experienced some passenger congestion in Terminal 5 departures, due to colleagues being instructed to self-isolate by NHS Test and Trace.

Images posted online show lines of travellers inside Terminal 5, with some describing it as “total chaos”.

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