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Published on: December 10, 2013
Viral Codetection and Clinical Outcomes of Infants Hospitalized With Bronchiolitis: A Multicenter Cohort Study
Gregorio Paolo Milani1,2, Andrea Ronchi3, Carlo Agostoni1,2
1From the Pediatric Unit.
Background:
The simultaneous identification of multiple respiratory viruses is common in infants hospitalized with respiratory tract infections. Respiratory syncytial virus (RSV) is one of the main pathogens in bronchiolitis, although codetection of rhinovirus, influenza and other respiratory viruses may occur in about one-third of cases. The relevance of viral codetection on disease severity is still controversial. This multicenter cohort study aimed to assess the clinical outcomes of infants under 24 months hospitalized with bronchiolitis, comparing those testing positive for RSV alone, RSV plus another virus and ≥2 viruses distinct from RSV.
Methods:
Data were collected across 13 hospitals in Lombardy, Italy, both in the prepandemic and pandemic years. Random effect regression models were also employed to test the association between 3 groups (infants testing positive for RSV alone, RSV plus another respiratory virus and no RSV but ≥2 respiratory viruses other than RSV) and course of bronchiolitis, adjusted for potential confounders.
Results:
Among 1788 infants, 86.7% tested positive for RSV alone, 6.9% for RSV plus another virus and 6.3% for ≥2 other viruses. Significant differences were found in clinical outcomes: infants with multiple non-RSV viruses had shorter oxygen supplementation, intensive care and hospital stay compared with those with RSV alone. Notably, codetection of RSV and another virus was associated with a higher risk of radiologically confirmed pneumonia, whereas detection of ≥2 non-RSV viruses was inversely associated with pneumonia.
Conclusions:
These findings point out that codetection of viruses other than RSV is associated with milder disease courses than detection of RSV alone in infants with bronchiolitis. On the other hand, patients with RSV and another virus are at higher risk of pneumonia than infants affected by RSV alone. Further research is required to understand the underlying mechanisms and optimize management strategies in infants with bronchiolitis testing positive for multiple viruses.
Insights
Infants hospitalized with bronchiolitis and multiple viruses showed milder outcomes than those with RSV alone. However, RSV with another virus increased pneumonia risk, unlike multiple non-RSV viruses.
Area of Science:
- Pediatrics
- Infectious Diseases
- Virology
Background:
- Multiple respiratory virus infections are common in infants with respiratory tract infections.
- Respiratory syncytial virus (RSV) is a primary cause of bronchiolitis, often with co-detections.
- The impact of viral co-detection on disease severity remains debated.
Purpose of the Study:
- To evaluate clinical outcomes in infants hospitalized with bronchiolitis.
- To compare outcomes based on RSV alone, RSV plus another virus, and multiple non-RSV viruses.
Main Methods:
- A multicenter cohort study involving 1788 infants under 24 months.
- Data collected from 13 hospitals in Lombardy, Italy.
- Random effect regression models analyzed associations between viral groups and bronchiolitis course.
Main Results:
- 86.7% had RSV alone, 6.9% RSV plus another virus, 6.3% multiple non-RSV viruses.
- Multiple non-RSV viruses correlated with shorter oxygen use, ICU stay, and hospitalization.
- RSV co-detection increased pneumonia risk; multiple non-RSV viruses inversely associated with pneumonia.
Conclusions:
- Non-RSV viral co-detections are linked to milder bronchiolitis courses compared to RSV alone.
- RSV co-infection with another virus elevates pneumonia risk.
- Further research is needed for optimal management of multi-viral infections in infants.
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