Fig. 1.

Confirmation of analytical sensitivity of the using clinical specimens. Specimens are depicted in descending order by copies/swab from left to right. Specimens depicted with purple circles were detected by the Quidel Sofia 2 while gold circles were undetected. The analytical sensitivity determined using dilutions of a pooled positive of 54,900 copies/swab is denoted by the dotted line. The arrow denotes the specimen that was negative on repeat testing and subjected to whole genome sequencing.