What is the most common cause of viral pneumonia in children and infants?

The most common cause of viral pneumonia in children and infants is Respiratory Syncytial Virus (RSV). This virus is highly prevalent in the pediatric population, particularly among infants and young children under the age of two. RSV is known for its ability to cause significant respiratory illnesses, including bronchiolitis and pneumonia, and it can spread rapidly in childcare settings and among family members.

The pathology associated with RSV pneumonia includes inflammation and obstruction of the small airways, leading to difficulties in breathing and gas exchange. The peak incidence of RSV infections typically occurs in the fall and winter months, correlating with seasonal outbreaks.

While influenza and parainfluenza viruses can also cause pneumonia in this age group, they are less common compared to RSV. Rhinovirus, primarily known for causing the common cold, does not typically lead to pneumonia in young children. Thus, RSV stands out as the leading cause of viral pneumonia due to its epidemiology and clinical significance in the pediatric population.