In this analysis of a prospective, multicenter study of children hospitalized with bronchiolitis, 925 had respiratory syncytial virus (RSV)-A and 649 had RSV-B. Overall, bronchiolitis severity did not differ by RSV subtype. However, among children with RSV-only bronchiolitis, those children with RSV-A had higher risk of intensive care treatment (odds ratio, 1.31; 95% confidence interval, 1.00-1.71; P = 0.048) when compared with those having RSV-B.
Clinical Profiles of Respiratory Syncytial Virus Subtypes A AND B Among Children Hospitalized with Bronchiolitis.