Study to Evaluate the Incidence of Hospitalizations and Respiratory Tract Infections in Premature Infants

The goals of this study are: * To estimate the incidence of hospitalization attributable to RSV within 150 days from enrollment in premature infants who are: * 32-35 weeks GA * less than 6 months of age at the start of the RSV season * not receiving palivizumab prophylaxis and not recommended to receive palivizumab according to the AAP guidelines * To estimate the incidence rate of hospitalization attributable to RSV in the other relevant study populations and time periods (e.g., Cohort 2, Cohorts 1 and 2 combined, and subgroups based on chronological age at the start of the RSV season, GA, etc. within 150 days from enrollment and other time periods based on RSV activity, etc.) * To estimate the incidence of RSV-associated MALRI in the study populations * To characterize the incidence and type of clinical interventions for MALRI in the study populations