Bangladesh Medical Research Council (BMRC)
Bronchiolitis is a viral inflammatory lesion of small airways. More than 70% cases are due to respiratory suncytial virus. Other pathogens are parainfluenza virus, adenovirus, rhinovirus, influenza virus and Mycoplasma pneumoniae. The occurrence is highest in mid winter to late spring. The peak incidence of bronchiolitis is 2-6 months of age and virtually all children become infected during first 3 years of life1, 2.