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The US is setting up a $1.7bn (£1.2bn) national network to identify and track coronavirus mutations of concern, which could spread and trigger another pandemic, the Biden administration have announced.

The investment will improve detection, monitoring, and mitigation of these variants by scaling up genomic sequencing efforts - a key step in containing the spread, the White House said.

“The original strain of Covid-19 comprises only about half of all cases in America today. New and potentially dangerous strains of the virus make up the other half,” the White House said in a statement.