The word “consumption” first appeared in the 14th century. For centuries, it meant any disease which wasted away the body. Over time, the term “consumption” was more specifically applied to tuberculosis. The German physician Robert Koch first identified the bacterium which causes tuberculosis in 1882. Tuberculosis can affect many parts of the body, such as organs, bones and the digestive tract, however the lungs are the bacterium's preferred target. Persons infected with tuberculosis usually took on an extreme paleness and experienced weight loss, fever, night sweats, and coughing up of blood. Between 1600 and 1800, the disease is estimated to have killed 25% of the population in Europe and in the United States.