Representative viremia results from 2 of the 10 plasma donors used in chimpanzee infection experiments (data from all 10 panels is presented in supplemental Figure 1). (A) TMA and viral load results over time from plasma donor panel 10081, who did not demonstrate intermittent blips of HCV RNA before detection of ramp-up–phase viremia. Numbers above bars represent the order in which aliquots were infused into chimps. Infusion 1 was part of a transmitting pool that was infused into chimp X355. Infusions 2-5 were each infused into chimp X331 at intervals of 9 weeks between infusions. ▴ indicates viral load in the ramp-up and post–ramp-up phase of HCV infection in donor 10081. (B) TMA and viral load results over time from plasma donor panel 10083 who manifested intermittent blips of HCV RNA reactivity during the eclipse phase of acute HCV infection. Both HCV RNA-negative “valley” and HCV RNA-positive “blip” samples were infused into chimp X331 (see Figure 1, experiment II). Numbers above bars identify aliquots and the order infused into chimps. Note that the units were infused in a different order than they were collected and that infusion 1 was part of a nontransmitting pool. ▴ indicates viral load in donor 10083.