Medical Editor January 30, 2024 How soon until you feel ill after catching someone else’s disease? From measles to colds, flu and Covid, our expert guide to when the symptoms will hit… and how long YOU are then infectious for – Daily Mail How soon until you feel ill after catching someone else’s disease? From measles to colds, flu and Covid, our expert guide to when the symptoms will hit… and how long YOU are then infectious for Daily Mail