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29th Nov 2022

Covid lab blunder linked to deaths of 20 people, investigators believe

Steve Hopkins

Researchers estimated the mistake would have led to 680 additional hospital admissions

A mistake at a lab which saw thousands of positive covid cases reported as negative could have led to the deaths of 20 people, new estimates on Wednesday suggest.

The error at a Wolverhampton lab meant around 39,000 PCR tests were reported as negative when they should have been positive between 2 September and 12 October 2021, with most of the cases being in the south-west of England.

“This represents around 10% of samples tested at the laboratory between 2 September and 12 October 2021 and 0.3% of all samples tested for NHS Test and Trace during this period,” the UK Health Security Agency (UKHSA) said on Wednesday.

The blunder meant many people would have continued with their daily lives and would not have self-isolated.

Experts from the UKHSA estimated the error led to about 55,000 additional infections, around 680 additional hospital admissions “that may not otherwise have occurred” and over “20 additional deaths in these most affected areas”.

The UKHS said the cause of the error “was the incorrect setting of the threshold levels for reporting positive and negative results of PCR samples for coronavirus”.

UKHSA’s serious incident investigation concluded that “no singular action or process” implemented by NHS Test and Trace could have prevented the errors within the lab, but it identified a range of ways to enable earlier detection of any similar laboratory errors wherever possible.

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