New York state Health Commissioner Mary Bassett will resign on Jan. 1, marking a departure of the highest-profile member of Gov. Kathy Hochul's cabinet before she starts her new four-year term. 

In a statement, Bassett said she plans to return to the Harvard Chan School of Public Health. 

"This was a very difficult decision. I have tremendous admiration for the work our staff has done during a very difficult year responding to COVID, mpox, polio and the day-to-day challenges of protecting New Yorkers’ health," she said. "I am leaving now so the next commissioner can have the chance to lead this great department for a full 4-year term under the leadership of Gov. Hochul."

Bassett, a former New York City health commissioner, replaced Howard Zucker a year ago, who had served as a holdover from Gov. Andrew Cuomo's administration. She was the first major appointment to Hochul's new administration, leading the sprawling public health department. 

Bassett was the primary official in charge of the state's response to a resurgence of COVID-19 cases, an ongoing rollout of vaccinations and booster shots as well as efforts to respond to an outbreak of polio and monekypox, now known as mpox.

In a statement, Hochul said she is "deeply grateful" to Bassett for her service leading the department over the last 12 months. 

"Throughout her time in my Administration -- from the onset of the Omicron variant and through mpox and polio outbreaks -- she has worked tirelessly to keep New Yorkers informed, healthy and safe," Hochul said. "I am proud that she brought her world-renowned expertise in equity and public health to the State Department of Health, and wish her the greatest success in her return to the Harvard Chan School of Public Health."

Her departure comes weeks after Division of Budget Director Robert Mujica submitted his resignation to take a job leading Puerto Rico's financial oversight agency.