Influenza
Conditions
Keywords
Severe influenza, biomarkers, respiratory microbiome, prognosis
Brief summary
Context: Seasonal influenza affects 2.5 to 3 million people each year in France, resulting in 1500 to 2000 severe cases seen in intensive care units. The severity of influenza is related to, among other things, its respiratory or neurological complications, observed especially in children. Early determination of the severity of influenza is a critical step to avoid in appropriate treatment and care for patients and to improve their survival. Viral, human but also environmental factors have been described as having an important role in determining this severity. Several studies suggest that the nasopharyngeal microbiome may be involved in the incidence and severity of respiratory viral infections. During influenza infection, the respiratory microbiota is significantly altered. In animal models, particularly murine models, the microbiota regulates the immune response to influenza virus infection. In a retrospective preliminary study, the investigators showed that the composition of the nasopharyngeal bacterial microbiota is different between children who develop a severe or moderate influenza. This difference was observed on respiratory specimens at admission to pediatric emergencies within two days of onset of symptoms. Hypotheses : * The respiratory microbiome is a determining factor in the clinical course of influenza infection (benign vs. severe with respiratory or neurological complication) * The respiratory microbiome can be used as a prognostic biomarker of the clinical course of influenza Originality: There are currently no clinical and / or virological markers to predict the clinical course of influenza infection. This study will define biomarkers of the respiratory microbiome to discriminate patients who will develop a severe influenza from those who will develop a moderate influenza. These prognostic biomarkers could be used to rapidly refer patients at risk to intensive care units, thus improving patient management and care. Moreover, at the fundamental level, this study will specify the role of the microbiome in the severity of influenza infection.
Interventions
BIOLOGICALCollection of nasopharyngeal specimen collected at D0, D1, D2 and D5.
Analyses will be performed on nasopharyngeal specimen collected at D0, D1, D2 and D5. Definition and validation of nasopharyngeal microbiome biomarkers (bacterial, viral, transcriptomic signature)
Sponsors
Hospices Civils de Lyon
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
No minimum to 5 Years
Healthy volunteers
No
Inclusion criteria
* Age \< 5 years * Seen in an emergency department with influenza confirmed by a positive test (polumerase chain reaction, rapide antigen detection test).
Exclusion criteria
* Presence of associated significant comorbidity (chronic respiratory, cardiac, neurological or metabolic pathology, prematurity, known immunodeficiency) * Documented non-respiratory bacterial infection * No consent * Patient not affiliated to a national health cover
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Definition and evaluation of a microbial signature discriminating patients developing severe influenza from those developing moderate influenza | Day 30 | On nasopharyngeal specimen collected at inclusion, a microbial signature will be defined as a limited number of bacterial genomic groups (OTU Operational Taxonomic Unit), that will help discriminate the 2 groups of patients (evolution toward a severe or a moderate influenza, evaluated at hospital discharge). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| sequencing the hypervariable regions of the 16S RNA on the longitudinal respiratory specimens | Day 1 | We will analyze the different dynamics of the composition of the microbiome associated with different influenza evolutions. The qualitative and quantitative evolution of the microbial species present in the respiratory specimens will be evaluated by sequencing the hypervariable regions of the 16S RNA on the longitudinal respiratory specimens performed on Day 1. |
Countries
France
Outcome results
None listed