Real-world effectiveness of perinatal RSV immunoprophylaxis: protocol for a test-negative case-control study

Area of Science:

• * Pediatric Infectious Diseases
• * Immunology
• * Public Health Virology

Background:

• * Respiratory syncytial virus (RSV) is a major cause of infant hospitalizations globally.
• * New immunoprophylactic interventions, including monoclonal antibodies and maternal vaccines, show promise in clinical trials.
• * Real-world data on intervention effectiveness and the influence of viral evolution and host factors are crucial for sustained RSV prevention.

Purpose of the Study:

• * To assess the effectiveness of novel RSV immunoprophylactic products in a real-world setting.
• * To investigate the impact of viral genetic diversity and host immune profiles on RSV protection.
• * To inform ongoing public health strategies for RSV prevention in infants.

Main Methods:

• * A 5-year test-negative case-control study involving infants up to 12 months old presenting with acute respiratory illness (ARI).
• * Cases are RSV-positive infants; controls are RSV-negative infants with ARI.
• * Data collection includes electronic health records, caregiver surveys, and immunization registries, supplemented by full-genome sequencing of RSV and immune profiling via blood samples.

Main Results:

• * This section will report on the estimated vaccine effectiveness using multivariable logistic regression.
• * Analysis will identify RSV variant lineages and potential immune-escape mutations.
• * Innate and adaptive immune responses associated with breakthrough RSV infections will be characterized.

Conclusions:

• * Findings will provide critical real-world evidence on the effectiveness of new RSV interventions.
• * Understanding viral evolution and host immunity will enhance RSV prevention strategies.
• * The study aims to ensure sustained confidence in global RSV prevention programs.