Background: Clinical and economic burden of infections due to respiratory syntactical virus (RSV) in children <2 years of age in Germany is still underestimated. Methods: In a retrospective health claims analysis, we identified RSV inpatient and outpatient episodes based on year-round specific RSV ICD-10 diagnoses or unspecified lower respiratory tract infection diagnoses during the RSV-season. High-risk groups were defined by ICD-10 codes. Hospitalization costs per patient were incurred between the beginning and end of an RSV episode. All-cause costs were compared to a matched control group without RSV infections based on age, sex, and prematurity in the inpatient and outpatient sectors. Results The incidence of hospitalization due to RSV was substantially higher in infants (21/1,000) than in toddlers (5.4/1,000). Most hospitalizations occurred in the first six months of life; the highest hospitalization incidences were observed in the second month of life (46/1,000). Infants with risk factors had a 2.4 times higher risk for hospitalization than those without. The economic burden per episode was high in the first 3 months of life and especially for those with risk factors and/or prematurity. However, overall annual resource utilization for the healthcare system was higher for healthy children with no underlying risk factors than for those with risk factors. Conclusion: RSV in children <2 years of age causes a considerable burden for the German healthcare system, both clinically and economically. Newborns, premature infants, children with chronic underlying risk factors are at highest risk for severe outcomes, but the overall disease burden affects healthy infants.

CB, LB, BH, and CvE are all employees of Pfizer in Germany, the sponsor of this study. SM and JR are employees of Gesundheitsforen Leipzig GmbH, paid by Pfizer to conduct the study. TT is an expert in the field of RSV and received an honorarium from Pfizer for input on the study design and review of the results.

This study was funded by Pfizer Pharma GmbH

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