Marc Lipsitch is Professor of Epidemiology and Director of the Center for Communicable Disease Dynamics at Harvard T.H. Chan School of Public Health. He received his DPhil from Oxford and was a postdoctoral researcher at Emory and CDC. His research combines microbiology/molecular biology, mathematical modeling, epidemiology, pathogen genomics, and statistical methods to study the evolution and population biology of pathogens as affected by immunity, vaccination, and antibiotic use. He has published on many aspects of COVID-19 and vaccine trial design, building on prior work on influenza, Streptococcus pneumoniae, antimicrobial-resistant pathogens, and other infectious agents. He is a member of the American Academy of Microbiology.