TOPLINE

Following the implementation of preventive strategies for respiratory syncytial virus (RSV) infection in France, hospitalization rates for bronchiolitis decreased significantly among infants with acute bronchiolitis. Infants who received nirsevimab had shorter hospital stays and required oxygen therapy less often than those who did not receive prophylaxis.

METHODOLOGY

• Researchers conducted a retrospective study at a university hospital in France to assess the effect of preventive strategies for RSV infection — the administration of nirsevimab and maternal RSV vaccination — on the clinical severity of bronchiolitis in hospitalized infants.
• They included 509 infants younger than 12 months hospitalized for a first episode of acute bronchiolitis during the four autumn or winter seasons in the preintervention (n = 292; 2021-2023) and postintervention (n = 217; 2023-2025) periods.
• They compared the preintervention and postintervention periods, and the outcomes were changes in markers of disease severity at admission such as respiratory rate, oxygen saturation, and signs of respiratory distress as well as indicators of clinical course during hospitalization including length of hospital stay and the need for oxygen therapy.

TAKEAWAY

• The use of oxygen therapy significantly declined from 70.9% in the preintervention period to 58.5% in the postintervention period (P = .005).
• Infants hospitalized during the postintervention period had a significantly shorter median length of hospital stay than those hospitalized during the preintervention period (3 days vs 5 days; P < .001).
• The proportion of infants who required oxygen therapy during hospitalization was lower among those who received nirsevimab than among those who did not (40.3% vs 67.1%; odds ratio [OR], 0.44; P = .023).
• RSV was detected in 83.8% of infants who did not receive preventive therapy compared with 43.8% of those who received nirsevimab (OR, 0.15; P < .001) and 50% of those whose mothers received RSV vaccination (OR, 0.19; P = .015).

IN PRACTICE

“These findings support the continued implementation of RSV immunoprophylaxis and underscore the importance of ongoing surveillance to monitor its long-term impact,” the authors wrote.

SOURCE

The study was led by Marine Tarizzo, Inserm U938, Centre de Recherche Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Hôpital Trousseau, Service de Pneumologie Pédiatrique, Sorbonne Université in Paris, France. It was published online on June 10 in Pediatric Pulmonology.

LIMITATIONS

The study’s retrospective and observational design precluded establishing a causal inference, and its single-center nature may have restricted the results’ generalizability. The study was not designed as a prospective birth cohort study and included only hospitalized cases, which may have limited the results’ representativeness.

DISCLOSURES

No funding or conflicts of interest were reported for this study.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.