Figure 1

Phylogenetic analytical design. The three-step process of estimating viral transmission between epidemiological characteristics that structure HIV transmission clusters within Houston/Harris County is summarized. In the first step, transmission clusters were identified. In the second step, a phylogenetic analysis was conducted to estimate the time of the most recent common ancestor for each cluster. In the third step, a joint estimation of transition rates of a single viral transition matrix for all clusters was conducted.