The Centers for Disease Control (CDC), the top US public health agency, witnessed its director announce her resignation on Friday, with her term coming to an end in June. 

A key personality in the Biden administration's response to Covid-19, Rochelle Walensky did not provide a reason as to why she quit her position but revealed that alleviating the coronavirus pandemic's weight on the country brought her term to a natural stop. 

"The end of the Covid-19 public health emergency marks a tremendous transition for our country, for public health, and in my tenure as CDC Director," she wrote in a letter to US President Joe Biden, which was released to the public.

She began her position in December 2020 with the aim of "leaving behind the dark days of the pandemic."

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"I have never been prouder of anything I have done in my professional career," Walensky wrote regarding her time as director, as she was a regular face on television relaying prevention measures and messages. 

In her previous path, she was a medical professor at Harvard from 2012 to 2020 and head of infectious diseases at Massachusetts General Hospital from 2017 to 2020. 

In light of this news, Biden released a statement saying that she "saved lives with her steadfast and unwavering focus on the health of every American," adding that "she led a complex organization on the front lines of a once-in-a-generation pandemic with honesty and integrity."

As of yet, a successor has not been confirmed nor named.