RSV Infection in One Year Olds: measuring economic and epidemiologic burden during five seasonal waves in Italy (2015-2020)

Problem considered: Respiratory Syncytial Virus (RSV) infection is a leading cause of respiratory illness, particularly among infants. The current research assesses the epidemiologic and economic impact of RSV infection in the Piedmont region among five seasonal waves between 2015 and 2020 among children younger than one year. Methods: A retrospective analysis of data from the hospital discharge database of infants under one year diagnosed with RSV infection was carried out. Hospitalisation costs were assessed through the Diagnosis Related Group (DRG) payment system. Multivariable logistic regression models were used for access to the Paediatric/Neonatal Intensive Care Unit and the average DRG code allocated at discharge. Time-trend analyses were performed for hospital admissions and related spending during the defined timeframe by computing the Annual Percent Change (APC). Results: There were 2980 hospitalisations, mostly males (54.7 %), mostly infants under six months of age (83.3 %), and 22.4 % non-Italian. The median cost for hospitalisation was ∼2800 euros. Multivariable regression models revealed a lower risk of assistance at the PICU/NICU for females (OR: 0.66, 95 %CI 0.50–0.86) and infants younger than 3 months (OR [3–6 months] 0.3, 95 %CI 0.21–0.44; OR [≥6 months] 0.17, 95 %CI 0.09–0.32). The allocation of a DRG code higher than 2800 Euros at discharge was lower for children between 3 and 6 months (OR: 0.82, 95 % CI 0.69–0.98) and non-Italian patients (OR: 0.71, 95 %CI 0.60–0.85). A significant upward trend of hospitalisation rate for males (26.4 %), females (22.4 %) and non-Italian (38.2 %) children was found. The spending trends for overall seasonal spending and DRGs over 2800 Euros resulted in a significant increasing APC (23.8 % and 27.9 %). Conclusion: A significantly upward epidemiological trend of RSV-related hospitalisation, with increasing admissions to PICU/NICU, and the rise of seasonal spending and hospitalisation average costs represent a valuable barometer for further investment in novel preventive measures.