Bronchiolitis epidemics in France during the SARS-CoV-2 pandemic: The 2020–2021 and 2021–2022 seasons

OBJECTIVES: We described bronchiolitis epidemics during the 2020–2021 and 2021–2022 seasons in France and their interaction with the COVID outbreak. PATIENTS AND METHODS: Data on family physician (FP) visits, emergency department (ED) visits, hospitalizations for bronchiolitis for children ˂ 2 years, and hospital virological data were analyzed and compared with previous seasons (2015–2020). RESULTS: The 2020–2021 epidemic arrived very late, and its impact was lower than in previous seasons (2015–2020) (FP visits: −23%, ED visits: −38%, and hospitalizations: −30%). The 2021–2022 epidemic started early (week 40) and lasted for a relatively long time (13 weeks). The impact was higher than in 2015–2020 (FP visits: +13%, ED visits: +34%, hospitalizations: +28%). CONCLUSION: Findings from the 2020–2021 epidemic may be linked to the implementation of non-pharmaceutical COVID-19 prevention measures. For 2021–2022, findings may be linked to an “immunity debt” resulting from the lower impact of the previous season.