America is ready to return to normal. Biden’s CDC chief isn’t so sure.

The newly installed director of the Centers for Disease Control and Prevention had one big request for agency employees at an all-hands meeting in March: Don’t talk to the press without permission.

Rochelle Walensky’s remarks caught many CDC scientists and officials off guard. Her boss, President Joe Biden, had campaigned on a promise to take control of the pandemic by letting science lead — a pledge that hinged almost entirely on allowing the nation’s top health experts, including those at the CDC, to speak publicly.

The CDC director’s request seemed...