When Covid-19 symptoms linger on

In one study, more than half of the Covid-19 patients had residual chest imaging abnormalities, like the areas of decreased lung capacity (white) seen in this MRI scan. — Bloomberg

Most Covid-19 patients have no symptoms or experience only mild to moderate symptoms.

Two-thirds of sufferers do not have any symptoms at all (asymptomatic), while 90% are symptom-free three weeks after their symptoms first appear.