Since the first case of COVID-19 in Wuhan, China, at the end of 2019, the pandemic has deeply changed the world. Our life, the economy of countries, our social interactions, and our relationship with science have been permanently modified. As scientists in direct contact with the SARS-CoV-2, within the Singaporean and international research consortium on COVID-19, we had to adapt and redirect our lab activities to address questions about the biology and immunology of this unknown virus and how our body can fight it. In this talk, I will describe our studies on the immunology of infection and after vaccination.