Dr. Rochelle Walensky, who has played a vital role in the administration’s pandemic response over the past two years, is leaving as director of the Centers for Disease Control and Prevention, a job she has held since President Joe Biden came into office in January 2021.

Her departure was confirmed on Friday by the White House in a statement from Biden that said Walensky “has saved lives with her steadfast and unwavering focus on the health of every American.”

“As Director of the CDC, she led a complex organization on the frontlines of a once-in-a-generation pandemic with honesty and integrity. She marshalled our finest scientists and public health experts to turn the tide on the urgent crises we’ve faced,” Biden said.