The guidance said it was not necessary to test people without symptoms of Covid-19 even if they had been exposed to the virus. It came at a time when public health experts were pushing for more testing rather than less, and administration officials told The Times that the document was a C.D.C. product and had been revised with input from the agency’s director, Dr. Robert Redfield.

But officials told The Times this week that the health department did the rewriting itself and then “dropped” it into the C.D.C.’s public website, flouting the agency’s strict scientific review process.

“That was a doc that came from the top down, from the H.H.S. and the task force,” said a federal official with knowledge of the matter, referring to the White House task force on the coronavirus. “That policy does not reflect what many people at the C.D.C. feel should be the policy.”