Which age group is most commonly affected by croup?

The age group that is most commonly affected by croup is infants and young children. Croup is primarily a viral infection that leads to inflammation of the airways, especially in young children aged six months to three years. This demographic is particularly vulnerable due to their smaller airways, which can become easily obstructed during episodes of inflammation.

In this age group, common viral infections, particularly those caused by parainfluenza viruses, can lead to symptoms such as a characteristic barking cough, hoarseness, and stridor. These symptoms arise due to the narrowing of the upper respiratory tract, which is more pronounced in younger children because of their anatomical structure.

While other age groups can experience respiratory illnesses, the incidence and severity of croup are significantly higher among infants and young children. This is due to their developing immune systems and the anatomical factors that contribute to the potential for airway obstruction.