Early estimates of nirsevimab immunoprophylaxis effectiveness against hospital admission for respiratory syncytial virus lower respiratory tract infections in infants, Spain, October 2023 to January 2024
Mónica López‐Lacort, Cintia Muñoz-Quiles, Ainara Mira‐Iglesias, F. Xavier López‐Labrador, Beatriz Mengual‐Chuliá, Carlos Ernesto Fernandez‐Garcia, Mario Carballido‐Fernández, Ana Pineda-Caplliure, Juan Mollar‐Maseres, Maruan Shalabi Benavent, Francisco Sanz, Matilde Zornoza Moreno, Jaime Jesús Pérez‐Martín, Santiago Alfayate-Miguélez, Rocío Pérez Crespo, E. Sánchez, Ana Isabel Menasalvas-Ruiz, Ma Cinta Téllez-González, S. Soto, Carlos Del Toro Saravia, Iván Sanz-Muñoz, José María Eirós Bouza, Vanesa Matías del Pozo, Marina Toquero-Asensi, Eliseo Pastor-Villalba, José Antonio Lluch Rodrigo, Javier Díez‐Domingo, Alejandro Orrico‐Sánchez
Abstract
The monoclonal antibody nirsevimab was at least 70% effective in preventing hospitalisations in infants with lower respiratory tract infections (LRTI) positive for respiratory syncytial virus (RSV) in Spain (Oct 2023-Jan 2024), where a universal immunisation programme began late September (coverage range: 79-99%). High protection was confirmed by two methodological designs (screening and test-negative) in a multicentre active surveillance in nine hospitals in three regions. No protection against RSV-negative LRTI-hospitalisations was shown. These interim results could guide public-health decision-making.