Reviewed by Erica Stohs, MD, MPH, University of Nebraska Medical Center
Following the recent COVID-19 surge in Southern California, investigators identified a novel SARS-CoV-2 variant, which accounted for 35% of all California strains and 44% of those in Southern California as of January 22, 2021. A random sample of SARS-CoV-2 isolates collected between November 11 and December 28, 2020 from Southern California was analyzed and sequenced, then compared to a publicly available database of globally representative samples (GISAID: 3/4/20-1/22/21). Local analysis identified 2 clusters, the largest, designated CAL.20C/S:452R, defined by 5 specified mutations, 1 of which confers resistance to monoclonal antibodies’ target on the spike protein. The effect on infectivity and disease severity has yet to be explored and, thus, the CAL.20 variant had not yet been deemed a variant of concern as of this publication. The emergence of this and future novel variants is not unexpected but highlights the importance of continued global surveillance and tracking. The CDC coordinates the effort to scale up and share US SARS-CoV-2 sequencing data and submit data to GISAID.