As the United States enters a critical phase in fighting the coronavirus pandemic, the country’s leading public health agency, the Centers for Disease Control and Prevention, appears to be on the sidelines, with its messages increasingly disrupted or overtaken by the White House.

Neither CDC Director Robert Redfield nor Anne Schuchat — the principal deputy director who has played key roles in the agency’s emergency responses stretching back two decades, including the 2009 influenza pandemic — have appeared on the podium during White House briefings by the coronavirus task force for more than a week.

Redfield did join a smaller briefing Wednesday afternoon, for the first time since March 9. He and three other task force members stood with President Trump and Vice President Pence for the day’s second task force appearance. The event, which lasted seven minutes, followed a task force meeting with nurses groups, according to the White House. Trump and Pence were the only ones who spoke, and they took no questions.

The CDC, which has come under fire because of protracted delays in the rollout of agency-developed test kits, has not conducted its own telephone briefings for reporters in more than a week. Recent CDC recommendations on school closures and mass gatherings were overtaken by different guidelines issued by the coronavirus task force, creating confusion, experts and officials said.

“It is confusing for the public to have CDC say no gatherings of more than 50 people, and the next day, the task force says no gatherings of more than 10 people,” said Tom Inglesby, director of the Johns Hopkins Center for Health Security. “If the information has changed, tell everyone why. Let’s make sure everyone is on the same page.”

It’s critical to hear from the CDC, the agency responsible for epidemic response, Inglesby said, as U.S. officials are calling on Americans to embrace drastic measures to minimize social contact to slow the spread of the virus. More than 13,000 cases have been reported by Thursday evening, with cases in every state, and 171 people have died, according to a Washington Post analysis.

“What are the scientists projecting going forward? What is the rationale for measures being taken? We’re kind of getting that by proxy,” Inglesby said, referring to briefings by the task force. “But it would be valuable to hear directly from the CDC.”

Redfield and Schuchat have testified before Congress and briefed members in closed sessions. But top CDC officials have rarely appeared on camera or been quoted in media interviews in recent weeks. The CDC has not conducted a briefing since March 9.

Its schedule has been disrupted because briefings by the task force are given priority. The White House events are often scheduled on short notice, according to a person familiar with the situation who spoke on the condition of anonymity to speak candidly. Many times, they take place right before or after previously scheduled CDC briefings. “There is chaos on timing,” the person said. As a result, the CDC has canceled briefings at the last minute, including one Tuesday on school closures that was scheduled with the school superintendents.

Katie Miller, a spokeswoman for Pence, who took over the task force from Health and Human Services Secretary Alex Azar late last month, said Redfield has been joining daily task force meetings. “CDC plays a critically important role,” she said. On Tuesday, when a reporter asked about Redfield’s absence, Trump said he was “doing a good job.”

Redfield is splitting his time between Atlanta, where the CDC is headquartered, and Washington, and he remains very much a part of the task force and is leading CDC’s response, a CDC spokesperson said.

Azar has blamed Redfield for the testing fiasco, several senior administration officials said, although some White House officials contend the blame is misplaced. Redfield is also not viewed as a strong public speaker by experts inside and outside the agency; he has had to issue corrections to misstatements in recent testimony before Congress.

Ever since Pence’s team took over the response, they have treated the outbreak as a public relations crisis as much as a public health crisis and have tightly managed communications of top health and administration officials, officials have said.

Public health experts say it’s not necessary for the CDC’s voice to come from the director. “It must be someone who can communicate clearly and tell people what they need to do,” said Asha George, executive director of the Bipartisan Commission on Biodefense.

Schuchat and Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, are among the senior officials most often cited by experts inside and outside the government who could play this role and who did so earlier in the outbreak, before Pence took over the response.

Former CDC director Tom Frieden has said in tweets and essays that the public needs to hear daily from Schuchat and Messonnier, both of whom have experience in outbreak responses. Messonnier warned several weeks ago, on Feb. 25, about the need to prepare for the kinds of measures the White House is urging, such as school closures and the cancellation of mass gatherings. She had been conducting most of the CDC briefings.

CDC has more than 1,000 people deployed for the response in Atlanta and in hard-hit states. About a dozen task forces within the agency are working on topics, from outbreak epidemiology to strategies to optimize face mask supplies for health-care workers because of worsening shortages.

The health officials who have been prominent recently are Deborah Birx, the White House’s coronavirus response coordinator and a retired U.S. Army physician and global AIDS expert, and Anthony S. Fauci, director of the National Institutes of Allergy and Infectious Diseases at the National Institutes of Health.

During the coronavirus task force briefings, Fauci and Birx take questions, provide updates about the pandemic and often announce new guidelines for Americans to follow. But the briefings are wide-ranging and cover a host of subjects, many of them focused on the economy, and they share the stage with Treasury Secretary Steven Mnuchin.

“Whether people are speaking from the White House or the NIH, we still want to hear from the CDC because we have trained the public to turn to the CDC,” said George, of the Bipartisan Commission on Biodefense.

“You want someone to explain to people why you’re making the decisions you are,” she said. “People will understand more about why something is canceled and what you’re trying to do.”

Alice Crites, Yasmeen Abutaleb, and Laura Meckler contributed to this report.

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