Dr. Anthony Fauci on Monday announced that he will be stepping down in December from his positions as director of the National Institute of Allergy and Infectious Diseases and chief medical adviser to the president.

He said he plans to pursue the next chapter of my career.

After more than 50 years of government service, I plan to pursue the next phase of my career while I still have so much energy and passion for my field, he said in a statement. I want to use what I have learned as NIAID Director to continue to advance science and public health and to inspire and mentor the next generation of scientific leaders as they help prepare the world to face future infectious disease threats.