Norovirus: tribulation and possible trial

Biological Role of Trace Elements and Viral Pathologies

The review presents summarized information on a new research avenue in biogeochemistry and geochemical ecology: relationships between the microcosm (viruses) and manifestations of animal and human pathologies. Some aspects of the biological action of selenium, zinc, copper and iodine, their influence on the manifestation and course of viral infections are considered. Attention is focused on the antioxidant, membrane-protective, boosting immunity, hormonal functions of trace elements, and on the antibacterial and antiviral properties of metallic copper and its compounds. The criteria currently applied in assessing the Se status of territories are compared with the incidence of COVID-19 and HIV in the population of the Russian Federation. In some cases, selenium deficiency in the environment is shown to be associated with a higher susceptibility to RNA viral infections. Emphasis is put on the necessity of improving the criteria for assessing the trace element status of territories and further studies in the geochemical ecology of viruses and their role in the biosphere.

Inactivation of norovirus on dry copper alloy surfaces

Noroviruses (family Caliciviridae) are the primary cause of viral gastroenteritis worldwide. The virus is highly infectious and touching contaminated surfaces can contribute to infection spread. Although the virus was identified over 40 years ago the lack of methods to assess infectivity has hampered the study of the human pathogen. Recently the murine virus, MNV-1, has successfully been used as a close surrogate. Copper alloys have previously been shown to be effective antimicrobial surfaces against a range of bacteria and fungi. We now report rapid inactivation of murine norovirus on alloys, containing over 60% copper, at room temperature but no reduction of infectivity on stainless steel dry surfaces in simulated wet fomite and dry touch contamination. The rate of inactivation was initially very rapid and proportional to copper content of alloy tested. Viral inactivation was not as rapid on brass as previously observed for bacteria but copper-nickel alloy was very effective. The use of chelators and quenchers of reactive oxygen species (ROS) determined that Cu(II) and especially Cu(I) ions are still the primary effectors of toxicity but quenching superoxide and hydroxyl radicals did not confer protection. This suggests Fenton generation of ROS is not important for the inactivation mechanism. One of the targets of copper toxicity was the viral genome and a reduced copy number of the gene for a viral encoded protein, VPg (viral-protein-genome-linked), which is essential for infectivity, was observed following contact with copper and brass dry surfaces. The use of antimicrobial surfaces containing copper in high risk closed environments such as cruise ships and care facilities could help to reduce the spread of this highly infectious and costly pathogen.