Figure 3.

Phylogenetic tree of the HA segment of IBV. Missouri samples from the 2019–2020 season that were collected for this study are labeled in red. Recommended vaccine strains are labeled in blue. The phylogenetic analyses were performed by using BEAST2 with a Hasegawa–Kishino–Yano (HKY) substitution empirical model, strict clock model, and coalescent constant population prior. Branches with a posterior probability $\ge$0.70 were labeled. The nomenclature of the genetic clades is adapted from that reported by the World Health Organization [51].