Every year, an outbreak of bronchiolitis is observed in emergency departments during the southern hemisphere summer. The 2016–2017 season was marked by a late onset of the bronchiolitis outbreak, likely due to unusually low rainfall for that season and the start of the school year.During the week of March 6–12, 2017, emergency departments on Réunion recorded a sharp increase (+49%) in cases of bronchiolitis among children under two years of age.In total, since the start of the outbreak, 301 cases of bronchiolitis in children under two years of age have been recorded, and 45% of these children were hospitalized for this condition. In light of this outbreak, it is important to remind the public of the appropriate preventive measures.