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

Euro Surveill. 2024 Feb;29(6):2400046. doi: 10.2807/1560-7917.ES.2024.29.6.2400046.

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.

Keywords: RSV; Respiratory Syncytial Virus; effectiveness; immunoprophylaxis; long-acting monoclonal antibodies; nirsevimab.

MeSH terms

  • Antibodies, Monoclonal, Humanized*
  • Antiviral Agents / therapeutic use
  • Hospitalization
  • Hospitals
  • Humans
  • Infant
  • Respiratory Syncytial Virus Infections* / drug therapy
  • Respiratory Syncytial Virus Infections* / epidemiology
  • Respiratory Syncytial Virus Infections* / prevention & control
  • Respiratory Syncytial Virus, Human*
  • Respiratory Tract Infections* / drug therapy
  • Respiratory Tract Infections* / epidemiology
  • Respiratory Tract Infections* / prevention & control
  • Spain / epidemiology

Substances

  • nirsevimab
  • Antiviral Agents
  • Antibodies, Monoclonal, Humanized