Rapid Covid testing in England may be scaled back over false positives

Exclusive: In leaked emails, Matt Hancock's adviser says there is urgent need for decisions' on asymptomatic testing

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Senior government officials have raised urgent" concerns about the mass expansion of rapid coronavirus testing, estimating that as few as 2% to 10% of positive results may be accurate in places with low Covid rates, such as London.

Boris Johnson last week urged everyone in England to take two rapid-turnaround tests a week in the biggest expansion of the multibillion-pound testing programme to date.