Friedrich August Johannes Loeffler (1852-1915) was a German bacteriologist at the University of Greifswald. He obtained his MD degree from the University of Berlin in 1874. He worked with Robert Koch from 1879-1884. Among his discoveries was the organism causing diphtheria (Corynebacterium diphtheriae) and the cause of foot and mouth disease (Aphthovirus). He also created Loeffler's serum, a coagulated blood serum used for the detection of the bacteria. He lived to be 62.