Rhinovirus/enterovirus contribution to respiratory-associated hospitalizations in adults during respiratory seasons in Spain: A 6-year prospective study

by Sandra S. Chaves, Valérie Bosch Castells, Ainara Mira-Iglesias, Joan Puig-Barberà, F. Xavier López-Labrador, Miguel Tortajada-Girbés, Mario Carballido-Fernández, Joan Mollar-Maseres, Germán Schwarz-Chávarri, Javier Díez-Domingo, Alejandro Orrico-Sánchez, Valencia Hospital Network for the Study of Influenza and other Respiratory Viruses (VAHNSI)

Understanding the burden of acute viral respiratory infection-related hospitalizations is crucial for guiding research and development. Unlike influenza, respiratory syncytial virus (RSV), or severe acute respiratory syndrome coronavirus 2, no pharmaceutical interventions exist for other respiratory viruses; therefore, their impact remains poorly characterized. This study aimed to investigate the association of current non-vaccine-preventable respiratory viruses, especially rhinovirus/enterovirus (RV/EV), on hospitalizations during the respiratory seasons.

Data from a prospective study that used multiplex polymerase chain reaction to conduct long-term surveillance on respiratory viruses in Valencia, Spain were analyzed. Patients aged ≥50 years hospitalized due to respiratory illness from 2014–15–2019–20 were included.

Respiratory viruses were detected in 35.2% (3,755/10,675) of hospitalized patients with acute respiratory illness. Influenza and RSV accounted for 22.1% of hospitalizations, RV/EV for 7.6%, and other non-vaccine-preventable viruses for 5.4%. Adults ≥75 years had average seasonal hospitalization incidence rates more than twice those aged 65–74 years and eight times those aged 50–64-year-olds. No significant differences in severity markers were observed among patients with or without virus identified, those aged ≥75 years had a 2–3 times higher mortality rate compared to younger age groups.

The potential impact of respiratory viruses on hospitalization rates among older adults, particularly those aged ≥75 years, highlights the need for targeted interventions to reduce healthcare system burden. Enhanced diagnostic capabilities and the development of next-generation preventive strategies, including vaccines and therapeutics, could improve patient outcomes and strengthen the resilience of the healthcare system during respiratory virus seasons.