The Lummi nation, a sovereign Native American tribe in the Pacific north-west, will soon open a pioneering field hospital to treat coronavirus patients, as part of a wave of strong public health measures which have gone further than many governments.

Tribal leaders have been preparing for Covid-19 since the virus first appeared in Wuhan, China, in late 2019, with medical staff beefing up emergency plans, reorganizing services and gathering medical supplies, including test kits and personal protective equipment.