Viral Etiology of Acute Bronchiolitis in The First Two Years of Life

Abstract

Acute bronchiolitis is the leading cause of lower respiratory tract infection in the first year of life and the most common cause of admission to the hospital for infants beyond the neonatal period. Hospitalization with bronchiolitis peaks between 3 and 6 months of life. Respiratory syncytial virus (RSV) is the major etiological agent responsible for bronchiolitis. Other causative viruses of acute bronchiolitis are human metapneumovirus, adenovirus, influenza A virus, influenza B virus, parainfluenza viruses types 1,2,3, coronavirus, enterovirus and bocavirus. Risk factors of acute bronchiolitis include Young age (3-6 months), secondary smoking, non exclusive breastfeeding in the first six months of life, family history of wheezy chest, preterm and cardiac infants. The present study aimed to detect the prevalence of respiratory syncytial virus, human metapneumovirus, adenovirus, influenza A virus, influenza B virus and parainfluenza viruses type 1 and type 3 as etiological agent of acute bronchiolitis, also aimed to detect the clinical phenotype of each virus. The present study included 380 infants in the first two years of life presented with picture of acute bronchiolitis. All children in the study were subjected to full medical history, thorough clinical examination. Both nasopharyngeal and throat swabs were taken from