Effectiveness of nirsevimab among infants in their first RSV season in the United States, October 2023-March 2024: a test-negative design analysis.

ABSTRACT:

Background

In August 2023, the Centers for Disease Control and Prevention recommended nirsevimab, a long-acting monoclonal antibody, for all U.S. infants aged <8 months entering or born during their first respiratory syncytial virus (RSV) season. Our aim was to estimate nirsevimab effectiveness against RSV-associated emergency department (ED) encounters and hospitalisation among U.S. infants during the 2023-2024 RSV season.

Methods

We conducted a test-negative analysis using electronic health record (EHR) data from 6 healthcare systems, including ED encounters and hospitalizations with a diagnosis of RSV-like illness (RLI) during October 8, 2023-March 31, 2024, among infants aged <8 months as of October 1, 2023, or born during the study period. Nirsevimab effectiveness was e

SUBMITTER: Payne AB 

PROVIDER: S-EPMC12485534 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature