Line Plot from Scientific Research

Specimen pools for sequencing from one tertiary sentinel facility with testing rate at 100 tests per 100,000 persons per day. In each plot, the operating curves of the expected day when the first Alpha variant sequence is generated are plotted for different proportions of specimens to sample for sequencing per day and turnaround times. We assumed that the Alpha variant was circulating at 1% initially, with wild-type SARS-CoV-2 in the background. We also assumed that positive specimens sampled within each week for sequencing are consolidated into a batch before they are referred for sequencing. Turnaround time refers to the time between collection of each weekly consolidated batch of positive specimens to the acquisition of its corresponding sequencing data. The vertical axes denote the number of days passed since the introduction of the Alpha variant (left) and its corresponding circulating proportion (right). The horizontal axes denote the proportion of positive specimens to sample for sequencing per day (bottom) and the corresponding mean number of sequences to be generated per week per 1,000,000 people over a 90-day epidemic period. All results were computed from 1,000 random independent simulations for each surveillance strategy. The shaded region depicts the s.d. across simulations.

DOI