To review the current landscape of intranasal influenza vaccines, highlighting recent advancements in vaccine formulation, delivery platforms, and the immunological mechanisms that underpin mucosal protection, particularly in addressing the limitations of traditional vaccines.
Key Findings:
Intranasal vaccines can induce both local and systemic immune responses, enhancing protection against influenza.
Live-attenuated influenza vaccines (LAIV) are currently the only licensed intranasal seasonal influenza vaccines but have variable performance in adults, particularly in terms of efficacy and safety.
Next-generation intranasal vaccine platforms aim to improve consistency, safety, and applicability across diverse populations, addressing the limitations of current vaccines.
Interpretation:
Intranasal vaccination presents a promising strategy to overcome the limitations of traditional intramuscular vaccines by enhancing mucosal immunity and offering practical advantages such as ease of administration, reduced logistical challenges, and increased patient compliance.
Limitations:
Variable performance of LAIV in adults and strain-dependent viral fitness, which may hinder public trust and uptake.
Clinical contraindications limit broader applicability of current intranasal vaccines, necessitating further research and development.
Conclusion:
Intranasal vaccination is a viable next-generation approach for influenza control, capable of inducing long-lasting and cross-protective immunity, while addressing key limitations of existing vaccination strategies.
