The senior scientist at USAMRIID, Jahrling, in many ways, reads as the central figure of The Demon in the Freezer; if this were a novel, he would be the best candidate for Preston’s protagonist. Jahrling’s efforts to induce variola in monkeys, to begin developing new medicines to fight smallpox, and to deal with the Amerithrax attacks are among the central elements of the second half of Preston’s text. An exceptional scientist in his own right, Jahrling promotes a research approach that puts him at odds with the similarly brilliant D.A. Henderson and guides Lisa Hensley as she establishes herself at the Institute. Yet his centrality to the narrative is not entirely a matter of science: even as he performs potentially life-saving research, Jahrling must attend to his wife, Daria, and his daughters, Kira and Bria. His activities are a reminder that real life continues, and sometimes intrudes, in the midst of biomedical crisis.

Henderson spearheaded the legendary Smallpox Eradication Program that confronted and uprooted all natural occurrences of the disease by the end of the 1970s. He spent the years following his victory on the staff of Johns Hopkins and then, in the wake of the World Trade Center attacks, became Director of the Office of Public Health Emergency Preparedness and Response.