As the effort of breathing increases, parents can see the nostrils flaring with each breath and the muscles between the ribs retracting as the infant struggles to inhale air. This effort is exhausting and very young infants may simply fatigue and quit breathing. Bronchiolitis is seasonal and appears more frequently in the fall and winter months. It is the most common reason infants are hospitalized during winter and early spring. The exact incidence of bronchiolitis is unclear but may be as high as ten cases per 1,000 in infants less than 1 year of age.
Some children have subclinical infections, that is, few or insignificant symptoms.
It is estimated that by the first year, half of all infants have been exposed to RSV and by age 2 almost all of them will have been exposed. Please read this Important notice . Please read it.