A heavily criticized recommendation from the Centers for Disease Control and Prevention last month about who should be tested for the coronavirus was not written by CDC scientists and was posted to the agency’s website despite their serious objections, according to several people familiar with the matter as well as internal documents obtained by The New York Times.

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 CDC product and had been revised with input from the agency’s director, Dr. Robert Redfield.

But officials told The Times this week that the Department of Health and Human Services did the rewriting and then “dropped” it into the CDC’s public website, flouting the agency’s strict scientific review process.

“That was a doc that came from the top down, from the HHS 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 CDC feel should be the policy.”

The document contains “elementary errors” — such as referring to “testing for COVID-19,” as opposed to testing for the virus that causes it — and recommendations inconsistent with the CDC’s stance that mark it to anyone in the know as not having been written by agency scientists, according to a senior CDC scientist who spoke on the condition of anonymity because of a fear of repercussions.

Adm. Brett Giroir, the administration’s testing coordinator and an assistant secretary at the Department of Health and Human Services, the CDC’s parent organization, said in an interview Thursday that the original draft came from the CDC but that he “coordinated editing and input from the scientific and medical members of the task force.”

Over a period of a month, he said, the draft went through about 20 versions, with comments from Redfield; top members of the White House task force, Dr. Anthony Fauci and Dr. Deborah Birx; and Dr. Scott Atlas, President Donald Trump’s adviser on the coronavirus. The members also presented the document to Vice President Mike Pence, who heads the task force, Giroir said.

He said he did not know why the recommendation circumvented the usual CDC scientific review. “I think you have to ask Dr. Redfield about that. That certainly was not any direction from me whatsoever,” he said.

The CDC emailed a statement from Redfield on Thursday night that said: “The guidelines, coordinated in conjunction with the White House Coronavirus Task Force, received appropriate attention, consultation and input from task force experts.

The question of the CDC’s independence and effectiveness as the nation’s top public health agency has taken on increasing urgency as the nation approaches 200,000 deaths from the coronavirus pandemic and Trump continues to criticize its scientists and disregard their assessments.

A new version of the testing guidance, expected to be posted today, has also not been cleared by the CDC’s usual internal review for scientific documents and is being revised by officials at Health and Human Services, according to a federal official who was not authorized to speak to reporters about the matter.

Similarly, a document, arguing for “the importance of reopening schools,” was also dropped into the CDC website by the Department of Health and Human Services in July and is sharply out of step with the CDC’s usual neutral and scientific tone, the officials said.

The information comes mere days after revelations that political appointees at HHS meddled with the CDC’s vaunted weekly reports on scientific research.

“The idea that someone at HHS would write guidelines and have it posted under the CDC banner is absolutely chilling,” said Dr. Richard Besser, who served as acting director at the Centers for Disease Control in 2009.

Dr. Thomas Frieden, director of the agency during the Obama administration, said, “HHS and the White House writing scientifically inaccurate statements such as ‘don’t test all contacts’ on CDC’s website is like someone vandalizing a national monument with graffiti.”

The vast majority of CDC documents are still carefully created and vetted and are valuable to the public, but having politically motivated messages mixed in with public health recommendations undermines the institution, Frieden said. “The graffiti makes the whole monument look pretty bad,” he said.

The current guidelines on testing, posted Aug. 24, said people without symptoms “do not necessarily need a test” even if they have been in close contact with an infected person for more than 15 minutes. Public health experts roundly criticized the CDC for that stance, saying it would undermine efforts to contain the virus.

“Suggesting that asymptomatic people don’t need testing is just a prescription for community spread and further disease and death,” said Dr. Susan Bailey, president of the American Medical Association, which usually works closely with the CDC

Some experts also said the recommendation appeared to be motivated by a political impetus to make the number of confirmed cases look smaller than it is.

Redfield later tried to walk back the recommendation, saying testing “may be considered for all close contacts,” but his attempts only added to the confusion. The language on the CDC’s website remained unchanged.

The Infectious Diseases Society of America, normally a close partner of the CDC, strongly criticized the recommendation on testing. “We’ve communicated that to the CDC and HHS, but I have not seen any signs that they’re going to change it,” said Amanda Jezek, a senior vice president at the organization.

At a congressional hearing Wednesday, Redfield said the agency was revising the recommendation and would post the revision, “I hope before the end of the week.” The revision was written by a CDC scientist but was being edited Thursday by the Department of Health and Human Services and the White House coronavirus task force, according to a federal official familiar with the matter.

Redfield also said at the Wednesday hearing that vaccines would not be widely distributed till next year and that face coverings were more effective than vaccines — assertions that Trump sharply criticized in a press briefing Wednesday evening, saying Redfield “made a mistake.”

The director has been described by CDC employees and outsiders as a weak and ineffective leader who is unable to protect the agency from the administration’s meddling in its science or from the public’s increasing mistrust in the agency.

“It feels like a setup,” the CDC scientist said, adding that many scientists within the agency feel it is being made to take the blame for the administration’s unpopular policies.

“CDC scientists are running scared,” Scott Becker, chief executive of the Association of Public Health Laboratories, said. “There’s nothing they can do that gets them out of this blame game.”

The CDC has often been criticized during the pandemic for being too slow and cautious in issuing recommendations for dealing with the coronavirus. That’s partly because every document is cleared by at least one individual on multiple relevant teams within the agency to ensure the information is consistent with the “current state of CDC data, as well as other scientific literature,” according to a senior agency scientist who spoke on the condition of anonymity.

In all, each document may be cleared by 12 to 20 people within the agency. “As somebody who reads them regularly and as somebody who has written things with CDC, I can tell you that the clearance process is painful, but it’s useful,” said Carlos del Rio, an infectious disease expert at Emory University. “It’s very detail oriented and very careful, and they, quite frankly, improve the documents.”

At least eight versions of the current testing guidance were circulated within the agency in early August, according to officials. But staff scientists’ objections to the document went unheard. A senior CDC official told the scientists, “We do not have the ability to make substantial edits,” according to an email obtained by The Times. The testing guidance was then quietly published on the agency’s website.

After the new guidance was published, media inquiries to the agency about its contents were directed to the Department of Health and Human Services, prompting speculation about its origins. CDC scientists were asked to make sure other pages on the website were consistent with the new recommendations. And a “talking points” memo circulated within the agency Sept. 1 instructed employees to say that the CDC was involved in developing the new guidance “with suggested comments and edits shared back with HHS and the White House Taskforce.”

That sort of instruction would not have been necessary had the document been written by the CDC staff, according to experts familiar with the agency’s procedures. “Never seen that talking point before,” a CDC scientist said.

The recommendation also asked people who “have attended a public or private gathering of more than 10 people (without widespread mask wearing or physical distancing)” to get tested only if they are “vulnerable.” The agency in fact recommends against people congregating in such groups, and its scientists avoid using the term “vulnerable” to describe at-risk groups, according to a CDC scientist familiar with the agency’s procedures.

The guidance is also nested within the section intended for health care workers and labs but addresses the general public and makes several references to “your health care provider.”

“We just looked so sloppy,” the scientist said. “That’s what kills me is it didn’t come from the inside.”

Experts who work closely with the CDC said the mistakes were obvious.

“You’re used to reading Shakespeare and all of a sudden now you’re reading a tabloid,” del Rio said. “There was political pressure on CDC in the past, but I think this is unprecedented.”