Jessica Wang's account of rabies in New York during the years between 1840 and 1920 describes the terror of this disease and the introduction of prophylaxis against it. Wang recognizes that we must understand infectious diseases both as products of biological agents as well as social events shaped by human emotions, experiences, disruptions, and institutional interventions, public and private. She nicely parses concepts of disease-identity as they changed over time, from early-nineteenth-century ideas about poisons to the emergence of germ theory in the final decades of the century.—Margaret Humphreys, Metascience