Indian American Surgeon General Vivek Murthy, appointed by former President Barack Obama, stepped down after he was asked to resign by the Trump administration as part of a move to appoint new leaders in key posts.
He was replaced temporarily by Rear Admiral Sylvia Trent-Adams, one of the first nurses to serve as Surgeon General. She has a doctoral degree in philosophy and a master of science in nursing and health policy, the New York Times reported on Friday.
"Today, Dr Murthy, the leader of the US Public Health Service Commissioned Corps, was asked to resign from his duties as Surgeon General after assisting in a smooth transition into the new Trump Administration," the US Department of Health and Human Services said in a statement.
Murthy will continue to serve as a member of the Commissioned Corps of the Public Health Service. He was confirmed as Surgeon General in December of 2014.
He said in a Facebook post: "Two years and four months ago, I was honoured to be sworn in as the 19th Surgeon General of the United States. For the grandson of a poor farmer from India to be asked by the President to look out for the health of an entire nation was a humbling and uniquely American story."
"I will always be grateful to our country for welcoming my immigrant family nearly 40 years ago and giving me this opportunity to serve."
The US Department of Health and Human Services already updated its official handles with the profile of Trent-Adams who has served the Public Health Services Corps for 24 years.
It was not immediately clear why Murthy was relieved from duty.
Murthy for years made headlines for calling gun violence a public health threat. In 2014, the National Rifle Association urged the Senate not to confirm him, the daily reported.
Murthy, 37, was born in England to parents from India and grew up in Miami, Florida.
His father is a physician too. Murthy is a graduate of Harvard College as well as the Yale University schools of medicine and business.