TABLE 2.

Summary of patents using chitosan in antiviral preparations

Use	Mechanism	Process	Activity	References
(I) Antiviral activity by physical mixtures	Mixing with organics	Polyvinylpyrrolidone, gelatine, photo‐initiator, sodium sulphate, ethanol, and acrylate glycidyl ether, etc.	Chitosan hydrogel antiviral liquid gloves	Qingliang et al. (2020)
		Chitosan mixed with grapefruit seed extract	Antiviral disinfectant activity against influenza virus, parainfluenza virus and rotavirus	Yong‐Chul et al. (2018)
		Chitosan succinate	Antiviral gel	Azat Rashidovich et al. (2010)
		Chitosan oligosaccharide pesticide	Against resistant watermelon virus disease and hot pepper virus diseases	Zhang et al. (2012)
		Chitosan and virus insecticide raw powder	Raw powder promotes the infection of insects with the virus so as to guarantee the insect killing	Zhenpu et al. (2017)
		Chitosan in combination of heparin or heparin sulphate	Prevention or treatment of infections in mammal including man caused by herpes virus	Olle et al. (2001)
	Mixing with inorganics	Copper‐containing chitosan fibres	Field of sanitary protection articles	Xianming et al. (2020)
		Chitosan particles with nickel ion	Adsorb enterovirus	Ya‐Ching et al. (2009)
(II) Antiviral activity by chemistry	Chitosan derivatives	Changing the structure of chitosan	Excellent antiviral action	Yonghong et al. (2004)
		Chitosan–arginine derivative	Against influenza A (H1N1), vaccinia virus (Copenhagen strain), herpes simplex 1 (SP7 strain) and encephalomyocardidits virus (B strain)	Baker and Wiesmann (2020)
(III) To prepare vaccines	Attenuated live vaccine	Chitosan microsphere	Against Porcine epidemic diarrhoea virus	Qigai et al. (2019); Fulai et al., (2018)
		Chitosan derivatives N‐2‐hydroxypropyldimethylethyl ammonium chloride chitosan/carboxymethyl chitosan	Newcastle disease attenuated live nanoparticle vaccines	Kai and Wang (2015)
		Nanoparticles	Influenza virus attenuated live vaccine	Ze (2012)
		Chitosan adjuvant intranasally	Pandemic influenza	Holdings (2001)