The guidelines are not mandatory and fall short of measures taken by other countries. But they appeared to draw on a report by British researchers warning that, without drastic action, 2.2 million people in the U.S. could die.

Here are the latest updates and maps of the outbreak.

In other developments:

“The Daily”: Today’s episode includes an interview with a doctor in Italy, one of the countries hit hardest by the pandemic.

What to know: Social distancing doesn’t have to be lonely. And if your children are learning from home, our writing prompts can help.

The Times is providing free access to much of our coverage, and our Coronavirus Briefing newsletter — like all of our newsletters — is free.

Another angle: On social media, outpourings of generosity are part of a shift toward direct giving. The writer Roxane Gay gave 20 people $100 each to help with their bills, and her pledge on Twitter inspired others to make similar donations.