Research progress of natural polysaccharides against respiratory viruses.

Respiratory infectious diseases caused by viruses pose a serious threat to human and animal health. In the search for effective antiviral agents, natural polysaccharides have emerged as promising candidates with significant potential. As natural bioactive compounds with low toxicity, polysaccharides exert antirespiratory virus effects through multiple mechanisms, including regulating immune response, inhibiting virus replication, and preventing virus adsorption and invasion. These multifaceted properties endow natural polysaccharides with broad therapeutic prospects, warranting further investigation. This review comprehensively summarizes the current understanding of the antiviral effects of natural polysaccharides and their derivatives while illustrating their underlying mechanisms, thereby providing a scientific foundation for the development of novel antiviral drugs and the advancement of natural polysaccharide-based therapeutics.