Frequency of apnea and respiratory viruses in infants with bronchiolitis.

The frequency of apnea in infants <12 months of age admitted with acute bronchiolitis was 5.16% (95% confidence interval: 3.94-6.72). Most commonly detected viruses in the 51 apneic infants were respiratory syncytial virus (33.3%), rhinovirus (13.7%) and viral coinfections (23.5%). Young age and prematurity were the main risk factors for apnea independent of the respiratory syncytial virus status. Non-respiratory syncytial virus infants had a higher rate of prematurity.