This is the Coronavirus Briefing, an informed guide to the pandemic. Sign up here to get this newsletter in your inbox.
Africa recorded its “worst pandemic week” yet, with cases surging and vaccines scarce, the W.H.O. said.
California’s Capitol building revived a mask rule after an outbreak infected four fully vaccinated people.
What we know about Lambda
In recent weeks, headlines and social media posts have begun to sound the alarm about the Lambda variant, which was first detected in Peru late last year.