Shibasaburo Kitasato

1852-1931

Japanese Physician and Bacteriologist

Shibasaburo Kitasato was a Japanese physician who became interested in studying microbes and their link to diseases. Under government sponsorship, he spent six years in Berlin working with Robert Koch (1843-1910). Kitasato is best remembered for his work on tetanus and diphtheria, successfully growing the first pure culture of the tetanus bacillus in 1889. Working with Emil von Behring (1854-1917), Kitasato demonstrated the power of blood serum as an antitoxin for treating both these diseases. In 1894 Kitasato discovered, simultaneously with Alexandre Yersin (1863-1943), the bacillus that causes bubonic plague.

Born in 1852 on Japan's southern island of Kyushu, Kitasato attended medical school first in Kumamoto and later in Tokyo. After graduating he went to work for the Central Sanitary Bureau. There he worked in the field of public health, studying cholera epidemics and working to prevent outbreaks of infectious diseases. In 1886 Kitasato was sponsored by his government to study and work in Berlin at the laboratory of the world famous Robert Koch. Koch had come to public attention in recent years for his groundbreaking work in developing the field of bacteriology. Koch had spent years perfecting methods for isolating and culturing particular germs, tracking down the microbes responsible for causing certain diseases. He had already established the sources of anthrax (1877), tuberculosis (1882), and cholera (1883) when Kitasato arrived in his lab.

Kitasato learned from Koch the careful and painstaking methods for culturing, studying, and experimenting with various microbes. His first major achievement came in 1889, when he succeeded in culturing the bacteria that causes lockjaw, the tetanus bacillus (Clostridium tetani). This was remarkable because Kitasato was the first to discover a means of growing anaerobic bacteria, germs that grow without contact with air. In addition, working with fellow researcher Emil von Behring, Kitasato discovered that the symptoms of tetanus were produced by a toxin put out by this microbe. The next year, after many experiments, Kitasato and Behring found that blood serum, the clearish liquid that separates out from blood when it is allowed to stand, from animals who had been infected and recovered worked as an antitoxin. By injecting this antitoxin into infected animals, their symptoms were cleared and recovery assured. The impact of this discovery was proven during World War I. Tetanus infections are picked up when open wounds come into contact with infected soil, and prior to this time soldiers died in large numbers as a result. Given as a precaution to virtually all wounded soldiers, the death from tetanus dropped dramatically during the war.

Upon returning to Japan in 1892, Kitasato established his own laboratory in Tokyo for continuing his studies of microbes and infectious diseases. This became the Institute for Infectious Diseases, and Kitasato received government funding to carry out his research and train other scientists.

In 1894 Kitasato was sent to Hong Kong, where an outbreak of bubonic plague was causing a high death toll. Kitasato set up a laboratory there and set to work tracking down the bacillus responsible. He succeeded in isolating the bacillus at virtually the same time as another scientist, Swiss researcher Alexandre Yersin. Yersin, trained in the French laboratory of Louis Pasteur, named the bacillus after his mentor, calling it Pasteurella pestis. This name remained official until 1971, when it was changed to recognize Yersin. It is now officially known as Yersinia pestis, though the old name is still frequently cited. Kitasato is given credit for the simultaneous discovery.

In 1914 the Japanese government made Kitasato's Institute for Infectious Diseases part of the Ministry of Education, a move that Kitasato disagreed with. He felt that his work had practical applications for public health and therefore should have been a part of the hygiene department under the Ministry of the Interior. As a result, Kitasato and his staff resigned their positions. He then went on to found a private laboratory known as the Kitasato Institute. This Institute is a non-profit organization still conducting important research today. At the same time as he was organizing his new institute, Kitasato accepted the job of creating and organizing a new medical faculty for the University of Keio.

In recognition of his contributions to the control of infectious diseases, Kitasato received numerous honors and awards not only in his own country but from many others as well. Upon leaving Germany to return to Japan, he was awarded the title of "Professor," the first non-German to receive this honor. He turned down several offers from abroad, opting to return to work in his native Japan. In 1917 he was appointed to the House of Peers by the Emperor Taisho and raised to the title of Baron in 1924. He died at home in 1931.

KRISTY WILSON BOWERS