The team interviewed over 1,700 people from the Augsburg area of Germany about their allergies. Led by Claudia Traidl-Hoffmann, Director of the University Center for Health Sciences at University Hospital Augsburg (UNIKA-T) and Professor of Environmental Medicine at TUM, the team differentiated between perennial or non-seasonal allergies — such as those triggered by house dust mites or animal hair, seasonal allergies caused by grass pollen for instance, and allergies to other substances such as food.