The purpose of a new study published in the Journal of Allergy and Clinical Immunology was to assess whether respiratory syncytial virus (RSV) or rhinovirus (RV) types are differentially associated with the future use of asthma control medication. This study enrolled children hospitalized for bronchiolitis at age <24 months, from 2008-2010, into a prospective, 3-center, 4-year follow-up study in Finland. Virus detection was performed; four years later, the current use of asthma control medication was examined. Overall, 349 (86%) children completed the 4-year follow-up. At baseline, the median age was 7.5 months—42% had RSV; 29% RV; 2% both, RSV and RV; and 27% had non-RSV/-RV etiology. Children with RV-A, RV-C and non-RSV/-RV bronchiolitis started the asthma-control medication earlier than those with RSV bronchiolitis. The results showed that four years later, 27% of patients used asthma control medication; both RV-A and RV-C etiology were associated with the current use of asthma medication. Meanwhile, the highest risk was found among patients with RV-C, atopic dermatitis and fever. The results indicated that severe bronchiolitis caused by RV-A and RV-C was associated with earlier initiation and prolonged use of asthma control medication. It was observed that the risk was especially high when bronchiolitis was associated with RV-C, atopic dermatitis and fever.