Application of Chitosan Microparticles against Human Norovirus

Abstract

Human norovirus (HuNoV) is the leading causative agent of foodborne outbreaks and is associated with the second most prevalent cause of waterborne infections in the United States. The goal of this research was to investigate the antiviral activity of chitosan microparticles (CM) against HuNoV GII.4 Sydney and its cultivable surrogate, Tulane virus (TuV), in suspensions mimicking fecally-contaminated water. CM was prepared by crosslinking chitosan molecules with sodium sulfate, and then its anti-noroviral activity was assessed using infectivity assay on TuV and RT-qPCR on TuV and HuNoV. A 3% CM suspension in PBS (pH 7.2) showed binding to TuV particles but with a negligible impact on virus infectivity (p>0.05). TuV and HuNoV suspended in fecal suspensions showed a 1.5-log10 reduction in genomic copies per ml following a 10-min contact time (p<0.05). Despite the negligible impact on viral infectivity, CM moderately binds to virus particles and helps purify environmental water by removing infectious virus particles. In this study, TuV served as a suitable surrogate for HuNoV by showing a similar log10 reduction in fecal suspension. Overall, the outcomes of thisresearch highlight the potential application of CM as a novel, natural treatment to minimize the spread of water-transmitted viral pathogens.