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PCR testing halted at laboratory amid fears around 43,000 false negatives


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Covid testing has been halted at a private laboratory in the West Midlands amid fears that around 43,000 people have received false negative results.

NHS Test and Trace has suspended PCR testing operations provided by Immensa Health Clinic Ltd at its Wolverhampton facility after an investigation into reports of people receiving negative results despite previously testing positive on a lateral flow.

The UK Health Security Agency said the errors related to test results given to people between September 8 and October 12, mainly in the South West of England.

It said there were no technical issues with test kits and advised people to continue to test as normal when necessary.

NHS Test and Trace estimates that around 400,000 samples have been processed through the lab but it insisted it was an isolated incident and that tests were now being processed at other facilities.

NHS Test and Trace is now contacting the people who could still be infectious to advise them to take another test. Close contacts who are symptomatic will also be advised to take a test.

In a statement, the UK Health Security Agency said: ‘NHS Test and Trace have suspended testing operations provided by Immensa Health Clinic Ltd at its laboratory in Wolverhampton, following an investigation into reports of people receiving negative PCR test results after they have previously tested positive on a Lateral Flow Device.

‘While investigations are underway into the precise cause, NHS Test and Trace estimate that around 400,000 samples have been processed through the lab, the vast majority of which will have been negative results, but an estimated 43,000 people may have been given incorrect negative PCR test results between 8 September and 12 October, mostly in the South West of England.

‘This is an isolated incident attributed to one laboratory but all samples are now being redirected to other laboratories. The number of tests carried out at the Immensa laboratory are small in the context of the wider network and testing availability is unaffected around the country.

‘NHS TT is contacting the people that could still be infectious to advise them to take another test. Close contacts who are symptomatic will also be advised to take a test in line with normal practice. Anyone with Covid-19 symptoms should book a PCR test. Those with a positive LFD test should get a follow up PCR test to confirm they have Covid-19.’

Dr Will Welfare, public health incident director at UKHSA, said: ‘We have recently seen a rising number of positive lateral flow results subsequently testing negative on PCR.

‘As a result of our investigation, we are working with NHS Test and Trace and the company to determine the laboratory technical issues which have led to inaccurate PCR results being issued to people.

‘We have immediately suspended testing at this laboratory while we continue the investigation.’

Andrea Riposati, chief executive of Immensa Health Clinic, said: ‘We are fully collaborating with UKHSA on this matter.

‘Quality is paramount for us. We have proudly analysed more than 2.5 million samples for NHS Test and Trace, working closely with the great teams at the Department for Health and UKHSA.

‘We do not wish this matter or anything else to tarnish the amazing work done by the UK in this pandemic.’

The shutdown of operations in Wolverhampton comes after a surge in false negative results from PCR tests carried out at a Government-run site at Newbury Showground in Berkshire.

West Berkshire Council confirmed people who took a PCR test at the site between October 3 and October 12 could have been given the wrong results and urged them to book in for a retest.

Graham Bridgman, the authority’s Executive Member for Health and Wellbeing, said: ‘We are aware there was an issue with some tests undertaken at Newbury Showground earlier this month, which has now been resolved.

‘We would urge any residents that are concerned about their results to book another test as soon as possible so we can continue to prevent the spread of the virus across the district.’