Which virus is primarily responsible for most cases of bronchiolitis?

Respiratory syncytial virus (RSV) is the primary virus responsible for most cases of bronchiolitis, particularly in infants and young children. This seasonal virus typically causes inflammation and congestion in the small airways of the lungs, leading to the characteristic symptoms of bronchiolitis, such as cough, wheezing, and difficulty breathing.

RSV is well-recognized for its impact on the pediatric population, often resulting in hospitalizations due to respiratory distress in young patients. The virus has a particularly high prevalence during the fall and winter months, contributing to its role as the leading cause of bronchiolitis.

While other viruses, such as influenza, adenovirus, and rhinovirus, can also cause respiratory illnesses in children, they do not account for as high a percentage of bronchiolitis cases as RSV. The distinct association of RSV with bronchiolitis underscores its clinical significance in emergency medicine and pediatrics, making it essential for healthcare providers to recognize and appropriately manage the condition.