Kiyoshi Shiga (志賀潔) was a Japanese physician and bacteriologist. He discovered the bacillus dysenteriae during a severe epidemic of dysentery in Japan.
In 1896 after graduating the Medical School of Tokyo Imperial University, Shiga started his medical career at the Institute for the Study of Infectious Diseases under Dr.Shibasaburo Kitasato (北里柴三郎) who discovered the tetanus bacillus.
In 1987 Shiga was able to isolate the organism now known as Shigella dysenteriae from faeces and intestinal wall in victims of dysentery. In 1900 he developed a dysentery antiserum.
Shigella was named after Kiyoshi Shiga (志賀潔).