What age group is most commonly affected by respiratory syncytial virus (RSV)?

Respiratory syncytial virus (RSV) predominantly affects infants and young children, especially those under two years of age. This age group is particularly vulnerable due to the immaturity of their immune systems and the anatomical and physiological characteristics of their respiratory systems, which can make them more susceptible to respiratory infections.

Infants often have narrower airways and a more reactive airway response, which can lead to significant respiratory distress when infected with RSV. The virus is a leading cause of bronchiolitis and pneumonia in this demographic, resulting in hospitalizations during peak seasons, typically in the fall and winter months.

While other age groups can contract RSV, including older children and adults, the severity of the disease and the likelihood of hospitalization are much higher in infants and toddlers. Understanding this epidemiology is crucial for early identification, prevention strategies, and appropriate clinical management for this at-risk population.