Thousands of our American ancestors were killed by vampires in the eighteenth and nineteenth centuries. By 1800, vampires could be blamed for nearly one-quarter of all deaths in North America and vampires remained the leading cause of death throughout the nineteenth century. This vampire did not resemble the clever Count Dracula of Bram Stoker’s imagination; this vampire’s cloak of invisibility was its smallness. It was so tiny that it could not be seen with the naked eye, which may explain its success as a mysterious killer. The mystery was solved in 1882, the year that Edward Koch announced his discovery of the tuberculosis bacillus. America’s vampires actually were—germs!

It is easy to identify the similarities between vampire folklore and the symptoms of tuberculosis. Vampires and victims of consumption, as pulmonary tuberculosis was then called, are the living dead. Vampires are consumption in material form, draining away life slowly and surreptitiously. Victims are walking corpses, red-eyed, pale and wasted, they embody disease and death. They suffer most at night. They awaken, coughing and in pain, sometimes describing a heavy feeling, like someone sitting on the chest. As the disease progresses, ulcers and cavities develop in the lungs and victims begin to cough up blood, which lingers at the corners of the mouth and stains the bedclothes. Family members are alarmed by what they see in the morning when they check on their dying loved one. Something is draining away the blood . . . the life. As the victim fades into death, others in the family begin to complain of the same symptoms. They wonder, Will this horror ever end? How can we stop it?