More than 20 people may have died due to errors at the Covid testing lab in Wolverhampton.

Over the past year, more than 20 people may have died due to errors in the Immensa Covid testing lab, which led to thousands of false negative test results, according to a UK Health Security Agency (UKHSA) report.

An incident at a private laboratory in Wolverhampton in October 2021 caused an estimated 55,000 additional Covid infections, 680 additional hospitalizations and 23 more deaths than expected.

The UKHSA has launched a ‘serious adverse events’ investigation after almost 40,000 PCR tests returned false negatives after sidestream positives.

The report found that Immensa employees had incorrectly set thresholds for reporting positive and negative PCR samples.

Immensa was a private laboratory contracted by NHS Test and Trace to perform PCR tests. Their operations were suspended after the incident came to light last October following local reports of people receiving false negatives after initially testing positive.

Richard Gleave, UKHSA Director and Principal Investigator, said: “During this investigation, we carefully reviewed existing arrangements to monitor contracts with private laboratories conducting impulse testing during this period. We concluded that staff errors at Immensa’s Wolverhampton laboratory were the direct cause of the misreporting of Covid-19 PCR test results in September and October 2021.

“In our opinion, there was no action that NHS Test and Trace could have taken to prevent this error from occurring in a private lab. However, our report contains clear recommendations to both mitigate the risk of these incidents recurring and ensure issues are resolved and investigated promptly.”