Figure 2: Phylogenetic tree of hepatitis C virus (HCV) E1 hypervariable region sequences (quasispecies) from six patients with incident genotype 1a HCV infection, and seven patients and two staff with prevalent genotype 1a HCV infection from the dialysis unit, compared to five Third National Health and Nutrition Examination participants with genotype 1a HCV infection. Maximum HCV quasispecies sequence identity for cluster A 99.3% to 100%, and 97.7% to 100% for cluster B.