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[Preprint]. 2021 Aug 4:2021.02.23.21252259. Originally published 2021 Feb 25. [Version 4] doi: 10.1101/2021.02.23.21252259

Extended Data Figure 2. Flowchart for SARS-CoV-2-positive nasopharyngeal swabs included in this study.

Extended Data Figure 2.

(top) During the study period of November 1, 2020 to May 1, 2021, 6,680 patients tested positive for SARS-CoV-2 at our hospital center and affiliated hospitals. From these 9,174 positive nasopharyngeal swabs, 3,433 swabs were stored as part of the Columbia University Biobank COVID-19 sample repository and available for this study. (left) PCR-based genotyping assays for E484K and N501Y (see Extended Data Fig. 1) were performed on 2,345 samples. We identified a significant proportion of samples with E484K (11%), later confirmed through sequencing to primarily fall within the B.1.526 lineage, and a number of samples with N501Y (3.9%), primarily within the B.1.1.7 lineage. (right) We performed whole-genome sequencing on 1,507 samples. Of these, 32% belonged to B.1.526 and the sublineages B.1.526.1 and B.1.526.2, while B.1.1.7 constituted a much smaller proportion of samples at our center (7.5%).