Study of Biomarkers of Immune Activation Associated with Symptoms and Immune Responses After Influenza Vaccination in Adults

This clinical fase IV study, using the administration of a single dose of a quadrivalent, inactivated, split influenza virus vaccine as biological intervention will mirror a study conducted at Imperial College, London, UK that will use a challenge with live virus as intervention. Comparison of the clinical observations and laboratory measurements generated in both studies will inform us about the similarities and differences in innate and adaptive immune responses elicited by both types of exposure to influenza virus antigen(s).