Welcome to the Coronavirus Briefing, a new newsletter from The New York Times. Sign up to get it by email here.

Every weekday, we’ll fill you in on the most important coronavirus developments, put it all in context, and point you to the most useful ways to be prepared.

In this inaugural edition, we’ll also catch you up on the story so far and the things you can do to help keep yourself and your community safe.

The virus is spreading across the U.S.

For weeks, as the virus spread in China and then beyond, U.S. officials kept a tight rein on screening: Only people who showed symptoms and had traveled to China or had a known exposure to another patient would be tested, and for the most part only by the Centers for Disease Control and Prevention.