The U.K. health department has suspended COVID testing at a private lab over an investigation into thousands of individuals possibly receiving false-negative results. NHS Test and Trace said it had halted operations at the Immensa Health Clinic lab in Wolverhamptom, where around 400,000 samples had been processed. While the “vast majority” will have resulted in ngative results, around 43,000 people may have received incorrect negative PCR test results between September 8 and October 12, mostly in the South West of England, the U.K. Health Security Agency said in a statement on Friday. The individuals in question had received negative PCR test results after previously testing positive on a Lateral Flow Device (LFD).

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