The InVS’s surveillance of bronchiolitis aims to describe the seasonal winter epidemic in the general population in terms of its dynamics and magnitude among children under the age of 2. The information produced (such as the week the epidemic phase begins) is intended both to inform and assist healthcare professionals in organizing patient care, as well as to aid decision-making and the organization of healthcare services for policymakers (continuity of care through city-hospital networks).In France, surveillance of seasonal bronchiolitis epidemics using data from physical therapist networks complements the syndromic surveillance conducted separately by the InVS based on prehospital activity data (emergency departments participating in the OSCOUR® network) and data on community-based emergency medical services (SOS Médecins associations). The complementary nature of the data from these three networks (emergency departments, SOS Médecins, and physical therapists) strengthens the analysis conducted using this data.