The Delta variant is currently the predominant variant circulating in Arizona, and has been identified in more than 99% of positive COVID-19 samples sequenced. CDC has reported that the Delta variant is more infectious, particularly in unvaccinated individuals, and spreads more rapidly than earlier variants of SARS-CoV-2. The Delta variant contains a number of mutations in the Spike protein. New mutations are continuously occurring; therefore several sub-lineages are evolving from the parent B.1.617.2 strain. Several AY sublineages have grown in prevalence, including AY.25, AY.44, and AY.103.

Delta in Arizona Genomes

* Lineages are assigned by Pangolin (O'Toole et al Virus Evolution).

Phylogenetic Timetree of Delta