RSV Seasonality in Martinique in Children Aged 2 Years or Less

Inclusion Criteria: * two years of age or younger * hospitalized for bronchiolitis in the pediatrics department of the University hospital of Martinique over the period 2007 to 2018 * with a confirmed virological diagnosis of RSV virus by ImmunoFluorescence (IF) from 01/01/2007 to 31/01/2016 and from 01/02/2016 by Reverse transcription polymerase chain reaction. * with a clinical diagnosis of bronchiolitis (presentation of suggestive clinical signs such as cough, respiratory distress associated with a febrile illness, with rhinopharyngitis in the previous days) * no opposition from the legal representative for the use of the data from the medical file in the context of the research. This non-opposition is documented in the patient's medical file Exclusion Criteria: * opposition from the legal representative for the use of the data from the medical file * Inability to inform legal representatives of the conduct of the research