Dr. Winnie Siu, MD, MSc, CCFP, FRCPC, is a public health physician and Senior Medical Advisor for the NACI Secretariat at PHAC, supporting the development of immunization guidance for influenza, RSV, vaccines in pregnancy and Indigenous Peoples. Previously, she worked on infectious disease surveillance and the COVID-19 response. Dr. Siu also practices as a family physician and is an Adjunct Professor at the University of Ottawa.