ABSTRACT
Selenium (Se) is a ubiquitous element akin to sulfur (S) existing in the Earth crust in various organic and inorganic forms. Selenium concentration varies greatly depending on the geographic area. Consequently, the content of selenium in food products is also variable. It is known that low Se is associated with increased incidence of cancer and heart diseases. Therefore, it is advisable to supplement diet with this element albeit in a proper form. Although blood increased concentrations of Se can be achieved with various pharmacological preparations, only one chemical form (sodium selenite) can offer a true protection. Sodium selenite, but not selenate, can oxidize thiol groups in the virus protein disulfide isomerase rendering it unable to penetrate the healthy cell membrane. In this way selenite inhibits the entrance of viruses into the healthy cells and abolish their infectivity. Therefore, this simple chemical compound can potentially be used in the recent battle against coronavirus epidemic.