RESPIRATORY SYNCYTIAL VIRUS: A SCOPING REVIEW OF PATHOPHYSIOLOGY, EPIDEMIOLOGY, ECONOMIC BURDEN, AND ADVANCES IN PREVENTION WITH IMPLEMENTATION CHALLENGES

Rajdeep Mazumdar*, Shalini Sunderam, Anit Kujur, Dewesh Kumar

ABSTRACT

Background: Respiratory Syncytial Virus (RSV) is a leading cause of lower respiratory tract infections globally, disproportionately affecting infants and older adults, with over 99% of childhood deaths occurring in low- and middle-income countries (LMICs). Despite its substantial burden, RSV remains underrepresented in national immunisation programmes, particularly in India. Methods: This scoping review followed the PRISMA framework. PubMed, Scopus, and Google Scholar were searched for literature published between 2015 and 2025 using terms including “RSV epidemiology,” “RSV vaccine,” “monoclonal antibody RSV,” “RSV burden India,” and “RSV implementation.” Studies addressing RSV pathophysiology, burden, prevention, and implementation in any setting were included; non-English publications and studies unrelated to human RSV disease were excluded. Findings were synthesised narratively. Results: RSV causes 33.1 million acute lower respiratory infections and up to 101,400 deaths annually in children under five, with LMICs bearing over 95% of this burden. India-specific data reveal RSV detection rates of 5–54% in hospitalised children. Recent approvals of nirsevimab, Abrysvo®, Arexvy®, and mResvia offer significant preventive efficacy (70–90%), yet affordability, cold chain requirements, regulatory delays, and vaccine hesitancy impede equitable access, especially in LMICs. Conclusion: RSV prevention now has a robust scientific foundation, but translating these advances into public health impact requires context-specific implementation strategies. India and LMICs must urgently address surveillance gaps, cost barriers, and programmatic integration within existing immunisation frameworks.

Keywords: Respiratory Syncytial Virus; RSV vaccine; nirsevimab; scoping review; LMICs; immunization.