Gaffky, Georg Theodor August (1850-1918)

German bacteriologist who isolated and cultured the typhoid bacillus Salmonella typhi, a bacterium that inhabits the intestine, in 1884. This led to improved diagnosis and prevention of typhoid fever.

Gaffky isolated and cultured the bacillus from the spleen in 1884. Until then, the study of the natural history of the bacillus had been obscured by all the other similar bacilli that make up the flora of the intestinal canal. Eventually, several different forms of the typhoid bacillus were fully characterized.

Gaffky was born in Hannover and graduated from the University of Berlin with an MD in 1873. He was fortunate to work as a research assistant in the laboratory of the bacteriologist Robert Koch 1880-85. Gaffky witnessed Koch's discovery of the micro-organisms responsible for tuberculosis and cholera, which inspired his own work on the typhoid bacillus discovered earlier by Eberth in 1880. Gaffky eventually succeeded Koch as the director of the Institute for Infectious diseases in Berlin.