Chronicles the tracking of a New York City outbreak of typhoid fever in the early 1900s and the efforts of local public health officials to stop the spread and pinpoint the source of the outbreak, which ended up being Irish immigrant Mary Mallon, an asymptomatic carrier of the bacteria that caused the disease. Includes photographs, sidebars, a list of famous typhoid victims, a glossary, a timeline, and a list of additional resources.

"Bonus! New chapter on the COVID-19 pandemic"--Cover.

Hidden -- Germ detective -- Death in Ithaca -- "An enemy that moves in the dark" -- Mysterious outbreak -- A threat to the city -- Pursuit -- Inside the white walls -- "The most dangerous woman in America" -- Into thin air -- Island exile -- The rest of the story -- Another deadly disease: COVID-19.