National Observatory of Children Hospitalized With Bronchiolitis
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- This is an observational study: the protocol does not assign a study treatment.
- Who it may be relevant to
- Registry conditions: Bronchiolitis. Basic parameters: 1 Day — 12 months · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- France
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Overview
OVNI3 is multicenter, non-interventional study based on the analysis of retrospective patient data extracted from medical records and collected as part of routine clinical care following hospitalization for bronchiolitis
Detailed description
Patients will be identified at each participating center if a diagnosis of bronchiolitis meeting the study inclusion criteria is documented in the medical record.
As this is a retrospective study based exclusively on previously collected health data (for hospitalization occurring between October 15, 2025, and February 15, 2026), and involving no additional procedures or modification of patient management, inclusion will be performed by the attending clinicians after hospitalization.
Following identification of the medical record, the clinician will send an individual information notice and a non-opposition form to the legal representatives.
Patient data will be collected in the absence of any expressed objection from one of the legal representatives.
Primary outcome measures
- Evaluate the nirsevimab effectiveness for RSV Bronchiolitis hospitalized vs Non-RSV Bronchiolitis in 2025/2026. [Time frame: 6 months]
Secondary outcome measures (3)
- Difference of effectiveness during the 2 seasons (2024/2025 vs 2025/2026) [Time frame: 2 years]
- Hospitalization Proportions according to Nirsevimab and RSV Status, based on different age Groups [Time frame: 6 months]
- Proportion of hospitalizations for bronchiolitis associated with other viruses (isolated or associated with RSV) [Time frame: 6 months]
Eligibility criteria
Inclusion criteria
- Children under 12 months
- Treated at one of the 12 study sites
- From October 15, 2025 to February 15, 2026
- For acute bronchiolitis defined according to current national and international recommendations
- Hospitalized
and
- RSV testing
- Known nirsevimab immunization status for the ongoing 2025/2026 season
Exclusion criteria
- Refusal to participate by the legal representative
- Maternal immunization with abrysvo after September 1st 2025
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Case-only
Study locations
France · 1 center
- ACTIV — Créteil
Identifiers
NCT: NCT07485907 · OVNI3