Dr. Hans de Graaf is a Pediatric Rheumatologist from the Netherlands. After medical graduation and tropical medicine training he has been working in Malawi as a tropical doctor for two years after which he was trained as a pediatrician under Prof. Frenkel in Utrecht, the Netherlands. Since 2013 he has been working in pediatric rheumatology together with Dr. Leahy in Southampton, UK. He has been part of the faculty of the annual USS course in pediatric rheumatology in Southampton since 2016 and has been doing research in USS in pediatric rheumatology. In 2021 he moved to the Netherlands where he is currently working as a pediatric rheumatologist. His current international research focuses on immunology during controlled human infection models using Malaria falciparum, Bordetella pertussis, Neisseria lactamica and Streptococcus pneumoniae.