At least 23 deaths might have been caused by a blunder at a privately run laboratory after thousands of positive Covid cases were reported as negative, public health experts have estimated.
The error, at the Immensa Health Clinic Ltd lab in Wolverhampton, led to about 39,000 PCR tests returning negative results between 2 September and 12 October 2021 when they should have been positive – mostly in the south-west of England.
Immensa Health Clinic was incorporated in May 2020 by Andrea Riposati, a former management consultant and owner of a DNA testing company, two months after a Covid pandemic was declared by UK authorities.
The government awarded Immensa a £119m contract in October 2020 to urgently “develop volume for PCR testing for Covid in line with test and trace requirements”.
The contract did not go to tender under rules allowing urgent responses to the pandemic.
The UK Health Security Agency (UKHSA) has estimated that the oversight led to about 55,000 additional infections, about 680 additional hospital admissions and 23 additional deaths.
UKHSA experts estimated that each person who received a false negative result went on to infect about two other people on average, though some would have continued to take measures to reduce the spread of infection.
NHS test and trace suspended testing operations provided by Immensa in October 2021 following reports of inaccurate results.
An investigation, conducted by the UKHSA, concluded the error occurred because staff at the lab set the threshold levels for reporting positive and negative results incorrectly.
Richard Gleave, the UKHSA director and lead investigator, said: “Through this investigation we have looked carefully at the arrangements in place for overseeing contracts of private labs providing surge testing during this time.
“We have concluded that staff errors within Immensa’s Wolverhampton laboratory were the immediate cause of the incorrect reporting of Covid PCR test results in September and October 2021.
“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.
“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.”
Jenny Harries, the UKHSA chief executive, said: “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.
“I fully accept the findings and recommendations made in this report, many of which were implemented as soon as UKHSA discovered the incident.
“These ongoing improvements will enhance our ability to spot problems sooner where they do arise. We are particularly keen to further improve how we work with local partners and directors of public health as rapid incidents like this unfold.”