Retail giant Amazon says it will build its own coronavirus testing lab to monitor the health of its staff, after cases were reported at more than 50 of its facilities across the US.

Some of those cases have involved multiple infected workers.

The company said it had assembled a team to build its own “incremental testing capacity”.

“Our operations sites and grocery stores are distributing masks to employees and conducting employee temperature checks,” the company said.

“A next step might be regular testing of all employees, including those showing no symptoms. Regular testing on a global scale across all industries would both help keep people safe and help get the economy back up and running.”