Zinc ions inactivate influenza virus hemagglutinin and prevent receptor binding

Abstract

Influenza A viruses (IAV) cause seasonal flu and occasional pandemics. In addition, the potential for the emergence of new strains presents unknown challenges for public health. Face masks and other personal protective equipment (PPE) can act as barriers that prevent the spread of these viruses. Metal ions embedded into PPE have been demonstrated to inactivate respiratory viruses, but the underlying mechanism of inactivation and potential for resistance is presently not well understood. In this study, we found that zinc ions directly impact the binding of influenza virus to host cell sialic acid receptors using hemagglutination assays. Quantifying this effect, we observed that zinc ions inhibit IAV receptor binding within 1 minute of exposure in a concentration-dependent manner. Maximum inhibition was achieved within 1 hour and irreversible for at least 24 hours. Serial passaging of IAV in the presence of zinc did not result in resistance. Overall, these findings are in line with previous observations indicating that zinc-embedded materials impact the IAV hemagglutinin and SARS-CoV-2 spike proteins, and support work toward developing robust, passive, self-cleaning antiviral barriers in PPE.