Jalink MB, et al. - Given that respiratory syncytial virus (RSV) is the leading cause of viral lower respiratory tract infections in infants, researchers explored the connection between serious RSV illness and onset of asthma up to 5 years of age in a cohort of preterm children and quantified this link. A retrospective preterm infant birth cohort (29 weeks 0 days to 35 weeks 6 days gestational age) was built from a provincial population-based database, and children were followed up for 5 years. Investigators found that the incidence rate of hospitalization with RSV (RSV-H) was 25/1000 infants among 3,916 premature children. Data reported that the adjusted hazards ratio for asthma in RSV-H infants was elevated at 1.58. Findings revealed that there is a moderate association between severe RSV infection, as measured by RSV-H in the first year of life, and asthma up to 5 years of age in prematurely born children.