Background.

Tuberculosis is a bacterial infection contracted by humans either through inhaling the bacteria or by eating meat from infected animals. Common symptoms are coughing, fatigue, and weight loss. Aging, poor nutrition, or other stresses on the body can free the bacteria, and clinical, or "open," tuberculosis results. Most frequently attacked are the lungs. As the victim coughs, the tubercles (nodules that the body forms around the bacteria as a defense mechanism) burst and particles are exhaled or released in sputum. Open cases can carry and spread the disease for months or years. Tuberculosis was long thought to be hereditary, but around 1880 the German Robert Koch discovered its bacterial cause. Today the disease can be controlled with drugs.

Tuberculosis in the 1900s.

An ancient disease, tuberculosis was long known as "consumption," since victims appeared to be consumed by their sickness. In 1900 the...