Frank Bowden, a specialist in the field of infectious disease and sexual health, looks at one bug at a time, weaving around them the stories of his patients and their families, the doctors and the difficulties they face and the horrors and successes of hospitals and health care programs. Through Bowden's own work in the field, we encounter Swine Flu, Golden Staph, SARS, Hepatitis, and HIV, and learn crucial lessons about public health and the human experience of disease.