The investigation would have revealed that an infected nurse had unintentionally transmitted the virus to 16 other people during a training session on June 30, despite most of the medical training posted for staff.
Hospital sources told the Guardian that everyone present was not two meters apart or covering their faces.
Meanwhile, a new study found that the rate of coronavirus infection in England had dropped considerably in the month before the lockout restrictions were lifted.
According to new research from Imperial College London, the nationwide infection rate halved every eight to nine days in May.
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