In this analysis of 2 prospective multicenter, multi-year cohorts of children hospitalized for bronchiolitis in the United States and Finland, 306 rhinovirus infections were genotyped. Rhinovirus-A and -C species were predominant in the US study, while rhinovirus-C species was predominant in the Finland study. In both cohorts, there were no significant between-species differences in clinical characteristics, including acute severity measures.