Most common agent responsible for bronchiolitis is:

Ans. is 'a' i.e., RSVIn infants, RSV causes a more severe lower respiratory tract illness, resulting in bronchiolitis or pneumonia.Clinically, the condition presents as cough, coryza, wheezing, rales, and low-grade fever (< 101degF). Bronchiolitis is usually self-limiting, but may cause a serious disease in premature infants, in immunocompromised hosts, and in individuals with underlying lung diseases. Reinfection with the virus occurs throughout the life. However, with advancing age and recurrent infection, the RSV infection is confined more to the upper respiratory tract than the lower respiratory tract.