The domestication of SARS-CoV-2 into a seasonal infection by viral variants

Ryley D McClelland; Yi-Chan James Lin; Tyce N Culp; Ryan Noyce; David Evans; Tom C Hobman; Vanessa Meier-Stephenson; David J Marchant

doi:10.3389/fmicb.2023.1289387

The domestication of SARS-CoV-2 into a seasonal infection by viral variants

Front Microbiol. 2023 Dec 20:14:1289387. doi: 10.3389/fmicb.2023.1289387. eCollection 2023.

Authors

Ryley D McClelland¹, Yi-Chan James Lin¹, Tyce N Culp¹, Ryan Noyce¹, David Evans¹, Tom C Hobman^{1

2}, Vanessa Meier-Stephenson^{1

3}, David J Marchant¹

Affiliations

¹ Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
² Department of Cell Biology, University of Alberta, Edmonton, AB, Canada.
³ Department of Medicine, University of Alberta, Edmonton, AB, Canada.

Abstract

Introduction: The COVID-19 pandemic was caused by the zoonotic betacoronavirus SARS-CoV-2. SARS-CoV-2 variants have emerged due to adaptation in humans, shifting SARS-CoV-2 towards an endemic seasonal virus. We have termed this process 'virus domestication'.

Methods: We analyzed aggregate COVID-19 data from a publicly funded healthcare system in Canada from March 7, 2020 to November 21, 2022. We graphed surrogate calculations of COVID-19 disease severity and SARS-CoV-2 variant plaque sizes in tissue culture.

Results and discussion: Mutations in SARS-CoV-2 adapt the virus to better infect humans and evade the host immune response, resulting in the emergence of variants with altered pathogenicity. We observed a decrease in COVID-19 disease severity surrogates after the arrival of the Delta variant, coinciding with significantly smaller plaque sizes. Overall, we suggest that SARS-CoV-2 has become more infectious and less virulent through viral domestication. Our findings highlight the importance of SARS-CoV-2 vaccination and help inform public policy on the highest probability outcomes during viral pandemics.

Keywords: COVID19; SARS; adaptation; coronavirus; seasonal infection; surrogates; virus.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by project grants from the Canadian Institutes of Health Research, and studentship funding for RM from Smiths Landing First Nation, NT (Grant No: CIHR: RN382934-418735 and CIHR: RN422598-443427).