RSV Disease Burden in Older Adults: An Italian Multiregion Pilot Study of Acute Respiratory Infections in Primary Care Setting, Winter Season 2022-2023.

Background: Respiratory syncytial virus (RSV) is a major cause of hospital admission in adults over 65, leading to severe complications and death. However, the disease burden in primary care for older adults in Europe is poorly understood. This pilot study aims to test a study protocol for evaluating the clinical burden of RSV in older adults in primary care settings in Italy.

Methods: In the 2022-23 winter season, we designed a study on RSV burden in individuals over 65 with acute respiratory infections (ARIs) in Liguria, Apulia, and Tuscany, Italy. Recruited patients underwent nasopharyngeal swabs for RSV confirmation and provided epidemiological and clinical data. RSV-positive patients completed follow-up questionnaires after 14 and 30 days regarding their clinical conditions, healthcare utilization, and socio-economic impact.

Results: We enrolled 152 patients with ARIs; 33 (21.7%) tested positive for RSV. The median disease duration was 14 days, with 3% hospitalized. Among RSV-positive patients, 87% received drug treatment, 52% of whom received antibiotics. After diagnosis, 74% required further GP consultations within 2 weeks. Additionally, 48% incurred extra costs. On day 30, 21% reported health complications or deterioration.

Conclusions: Our pilot study highlights the need for an ARIs surveillance system for older adults in primary care. This is crucial for defining vaccination strategies to reduce the disease burden on these patients and the healthcare system. Moreover, these data are essential for assessing costs and parameters for cost-effectiveness models, facilitating informed decisions in public health planning and resource allocation.