Under the Microscope with David Weber: SARS-CoV-2 variants – Any Cause for Concern?
This Week’s Review:
COG-UK update on SARS-CoV-2 Spike mutations of special interest Report 1, prepared by COVID-19 Genomics UK (COG-UK), addresses the emergence of the new SARS-CoV-2 variants.
SARS-CoV-2 is an enveloped RNA virus. RNA viruses, such as SARS-CoV-2 and influenza A, may undergo mutations (i.e., a change of a nucleotide in the virus RNA genome, a subset of which results in a change in amino acid) which can result in a deletion or insertion in the virus genome. Mutation in the viral genome of SARS-CoV-2 can lead to virus variants (i.e., a distinct virus).
The possible implications of a new SARS-CoV-2 variants are as follows:
- ability to spread more rapidly in humans
- ability to cause either milder or more severe disease in humans
- ability to evade detection by some diagnostic tests
- decreased susceptibility to therapeutic agents such as monoclonal antibodies
- ability to evade vaccine-induced immunity.
Recently, a variant with increased transmissibility has been reported to be common in the United Kingdom, and a few patients with this variant have been reported in the United States. Variants have been reported with the ability to evade detection by some diagnostic tests; variants have also been reported with likely decreased susceptibility therapeutic agents such as monoclonal antibodies. No variants have been reported that lead to milder or more severe disease.
To date, it appears that current variants will NOT impair the vaccine response which is polyclonal, but further research is underway. It is NOT expected that any of the mutations will alter the basic nature of SARS-CoV-2 and hence it is expected all SARS-CoV-2 will remain susceptible to currently recommended antiseptics and disinfectants. Furthermore, it is unlikely that variants would be more environmentally stable. The Centers for Disease Control is planning to enhance its surveillance of SARS-CoV-2 variants.
Under the Microscope with Dr. David Weber explores what’s new in industry literature and provides a synopsis, along with key takeaways.
Reference: COG-UK update on SARS-CoV-2 Spike mutations of special interest Report 1 Prepared by COG-UK, 20thDecember 2020. Available at: https://www.cogconsortium.uk/wp-content/uploads/2020/12/Report-1_COG-UK_20-December-2020_SARS-CoV-2-Mutations_final_updated2.pdf