Characterization of Viral Populations by Using Circular Sequencing

With the enormous sizes viral populations reach, many variants are at too low a frequency to be detected by conventional next-generation sequencing (NGS) methods. Circular sequencing (CirSeq) is a method by which the error rate of next-generation sequencing is decreased so that even low-frequency viral variants can be accurately detected. The ability to visualize almost the entire genetic makeup of a viral swarm has implications for epidemiology, viral evolution, and vaccine design. Here we discuss experimental planning, analysis, and recent insights using CirSeq.