Paul Bastard, MD-PhD, is currently working in the Pediatric Hematology and Immunology department of Necker Hospital for Sick Children (AP-HP, Paris, France), while also doing research in the Necker branch of the laboratory of Jean-Laurent Casanova, at the Imagine Institute (University of Paris Cité, INSERM) and the Rockefeller University (New York, USA). From 2020 onwards, he identified the role of auto-Abs to type I IFNs in the pathogenesis of more than 15% of cases of life-threatening COVID-19 pneumonia, and in several other severe viral diseases. His research currently focuses on the causes and consequences of autoantibodies against type I interferons and cytokines, including in cancer, and on their genetic determinants.