Dr. Rachel Levine was sworn in as the admiral of the U.S. Public Health Service Commissioned Corps Tuesday morning, making her the first openly transgender four-star officer.

Levine, the former secretary of health in Pennsylvania, made history in March by becoming the first openly transgender federal official to be confirmed by the U.S. Senate, under the Biden Administration.

The U.S. Public Health Service Commissioned Corps are known as “America’s Health Responders” and respond to health emergencies on behalf of the federal government, including administering COVID-19 vaccines and responding to natural disasters.

Dr. Levine became the Corps’ first female four-star admiral and the sixth four-star admiral in the history of the service, according to the Washington Post.

In an interview, Levine told Washington Post that her new position as an admiral was “not just symbolic.”

“I’m doing this because of my dedication to service … [and] with the utmost respect and honor for the uniform that I will be wearing,” Levine said.