Staff errors at a privately run Covid-19 testing laboratory in England’s West Midlands in 2021 meant that 39,000 positive PCR tests were reported as negative, according to the UK Health Security Agency.
Scientists at the disease protection agency estimated that the blunders led to 59,000 infections, around 680 hospitalisations and “just over 20 additional deaths”.
The UKHSA released the findings of its investigation of the lab, operated by Immensa Health Clinic, on Tuesday. It also published a scientific analysis of the likely consequences of people who should have isolated behaving normally because they wrongly believed that they were free of infection.
Immensa, a UK subsidiary of Italy-based Dante Labs, was granted more than £180mn in contracts by NHS Test and Trace over the course of the Covid pandemic. Immensa was contacted for comment.
UKHSA suspended testing at the Wolverhampton laboratory on October 12 2021 following reports of inaccurate results. The investigation found that these were caused by incorrect setting of threshold levels for reporting positive and negative results of PCR tests by staff.
The additional Covid cases, hospitalisations and deaths caused by staff errors at the lab in September and October 2021 were calculated by epidemiological modelling. It is not possible to identify individuals who suffered as a result.
Around 10 per cent of samples tested in the lab over the previous six weeks were wrongly reported, UKHSA said, representing 0.3 per cent of all samples tested for NHS Test and Trace during the period.
“Through this investigation we have looked carefully at the arrangements in place for overseeing contracts of private labs providing surge testing during this time,” said Richard Gleave, UKHSA director and lead investigator.
“It is our view that there was no single action that NHS Test and Trace could have taken differently to prevent this error arising in the private laboratory,” he said. “However, our report sets out clear recommendations to both reduce the risk of incidents like this happening again and ensure that concerns are addressed and investigated rapidly.”
The agency said it would enhance surveillance of laboratory results so discrepancies could be identified and investigated as soon as possible.
“UKHSA is committed to being a transparent, learning organisation and this means investigating where things have gone wrong and working out how things can be improved,” said Jenny Harries, the agency’s chief executive.
“I fully accept the findings and recommendations made in this report,” she added. “These ongoing improvements will enhance our ability to spot problems sooner where they do arise.”