White House sees program as a more elastic testing infrastructure that will accommodate surges and remain on standby

Nearly half of 500m free Covid-19 tests the Biden administration made available to the US public have not been claimed, as cases plummet.

Wild demand swings have been a subplot in the pandemic, from vaccines to hand sanitizer and tests. On the first day of the White House test giveaway in January, the covidtests.gov website received more than 45m orders. Now officials say fewer than 100,000 orders a day are coming in for packages of four free rapid tests per household, delivered by the US Postal Service.