OBJECTIVES: To determine the impact of viral lower respiratory tract infections (LRTIs) in infancy including rhinovirus (RV) and infancy respiratory syncytial virus (RSV), on school age pulmonary function and healthcare utilization in prematurely born children. WORKING HYPOTHESIS: School age respiratory outcomes would be worse and healthcare utilization greater in children who had viral LRTIs in infancy. STUDY DESIGN: Prospective study. SUBJECT SELECTION: A cohort of prematurely born children who had symptomatic LRTIs during infancy documented, was recalled. METHODS: Pulmonary function was assessed at 5 to 7 years of age and health related costs of care from aged one to follow-up determined. RESULTS: Fifty-one children, median gestational age 33(+6) weeks, were assessed at a median (IQR) age 7.03 (6.37-7.26) years. Twenty-one children had no LRTI, 14 RV LRTI, 10 RSV LRTI, and 6 another viral LRTI (other LRTI). Compared to the no LRTI group, the RV group had a lower FEV1 (P = 0.033) and the other LRTI group a lower FVC (P = 0.006). Non-respiratory medication costs were higher in the RV (P = 0.018) and RSV (P = 0.013) groups. Overall respiratory healthcare costs in the RV ( pound153/year) and RSV ( pound27/year) groups did not differ significantly from the no LRTI group ( pound56/year); the other LRTI group ( pound431/year) had higher respiratory healthcare costs (P = 0.042). CONCLUSIONS: In moderately prematurely born children, RV and RSV LRTIs in infancy were not associated with higher respiratory healthcare costs after infancy. Children who experienced LRTIs caused by other respiratory viruses (including RV) had higher respiratory healthcare costs and greater pulmonary function impairment.