President Biden's coronavirus response coordinator Jeff Zients will depart in April to return to private life, the White House announced Thursday.

Zients, who helped coordinate the largest vaccination campaign in American history through multiple waves of the pandemic, will be replaced by Ashish Jha, a public health expert who currently serves as dean of the Brown University School of Public Health.

"Jeff spent the last 14 months working tirelessly to help combat COVID. He is a man of service and an expert manager. I will miss his counsel and I’m grateful for his service," Biden said in a statement.

Zients's deputy Natalie Quillian will also leave the administration in April, according to a White House official.

The departure of Zients is a sign the White House views the crisis phase of the pandemic as over, and is shifting to a longer-term strategy. Jha is a practicing internist and public health researcher who has been on the front lines of the COVID-19 response.

Zients is a management consultant with experience in rapid response political situations, including leading the team that fixed the healthcare.gov website after a disastrous launch.

The White House is in the midst of a delicate balancing act as officials try to balance getting America back to a semblance of normalcy while also grappling with the continued uncertainty and threat of the coronavirus.

"Thanks to all the progress we’ve made, Americans are safely moving back to more normal routines, using the effective new tools we have to enable us to reduce severe COVID cases and make workplaces and schools safer," Biden said. 

But he added that "our work in combatting COVID is far from done." More people need to be vaccinated and boosted, a vaccine needs to be approved for children under five years old, and vulnerable populations still need to be protected.

"As we enter a new moment in the pandemic — executing on my National COVID-19 Preparedness Plan and managing the ongoing risks from COVID — Dr. Jha is the perfect person for the job," Biden said.

Zients's departure also comes as the White House is struggling to secure more than $22 billion from Congress to fund the nation's future response. Administration officials have warned without the money it requested, there will not be enough money to purchase additional tests, treatments or vaccines.

Congress was poised to pass $15 billion as part of a government funding package last week, but it fell apart when House Democrats objected to paying for it in part by taking back $7 billion in federal money that had been allocated to the states.

The lack of funding for the future could put the U.S. at risk if another deadly variant begins spreading. While infections are on a downward trajectory in much of the country, they are rising in parts of Europe and Asia, which is often a predictor of what will happen in the U.S.

Jha has generally been a voice of optimism throughout the pandemic, even as he has called for aggressive responses. He has been a constant presence on cable news, and on Twitter, for much of the last two years. 

On Thursday, Jha tweeted he was "honored" to have the opportunity to serve.

"For all the progress we’ve made in this pandemic (and there is a lot), we still have important work to do to protect Americans’ lives and well being," Jha said.

"We are in so much of a better place with vaccines, diagnostics, increasingly, therapeutics, and much more," Jha said, but added that "We are not done" and are "very likely to see more surges of infections."

In a statement, Brown University said Jha will take a short-term leave for the temporary special assignment.

--Updated at 8:56 a.m.