Our results demonstrate that children who experience severe RSV bronchiolitis in infancy
are at significantly increased risk for asthma during the first 6 years of life and that
symptoms generally persist as children grow toward school age. Aeroallergen sensitization,
repeated wheeze, and maternal asthma were strongly associated with the development and
persistence of asthma in our cohort, whereas white race and day care attendance were
associated with decreased likelihood of asthma. The presence of increased CCL5 expression
in the nasal epithelia during bronchiolitis is strongly predictive of asthma at school age, with
much greater sensitivity and specificity than clinical features, including maternal asthma.
Physicians are encouraged to closely monitor children after severe RSV bronchiolitis, to
provide additional guidance to children and families with additional risk factors (genetic and
environmental) for asthma, and to test at a young age for sensitization to common allergens.
Additional research is necessary to evaluate whether these factors remain significant as these
children grow older because our data and those of several previous studies
3,6,7,9
have shown
that characteristics associated with persistence of asthma after RSV bronchiolitis vary with
the child's age.