Wartime report shows Unit 731 used animal blood transfusion in humans

Experts from the Exhibition Hall of Evidences of Crime Committed by Unit 731, a museum located in Harbin, Heilongjiang province, interpreted on Tuesday an original report written by a military doctor of the Imperial Japanese Army, providing a rare and graphic account of its biological warfare research and human experimentation during World War II.

The report, written by Tsutomu Saito, was made public at a Japanese military medical conference held in March 1940, indicating that the Imperial Japanese Army had repeatedly conducted experiments in China involving the transfusion of animal blood into humans during the war.

The report was published in August 1940 in the Japanese journal Army Medical Corps — one of the most representative military medical journals in modern Japan, with strong political and military characteristics in content, according to Jin Shicheng, director of the museum's education and publicity department.

The journal was published monthly since its inception in March 1903 until it ceased publication in August 1945. It mainly published cutting-edge military medical research papers written by members of the Army Medical Corps, introduced the latest foreign research results, and reported on the activities of various local corps.

The report shows that in 1938, the Imperial Japanese Army used the blood of five different animals — horses, sheep, dogs, rabbits, and chickens — to conduct live experiments on 23 prisoners of war.

The report records that to find a solution for battlefield casualties requiring blood replenishment, the army discussed several methods such as transfusing preserved blood, serum, dried blood, and cadaver blood.

Saito advocated for the transfusion of animal blood, with horse blood as the first choice.

The document indicates that the experimenters injected individuals with animal blood or serum — specifically including large-volume transfusions of horse blood into individuals in critical conditions of blood loss, and injections of chicken blood into humans to observe how long it remained in the human body.

It also recorded adverse reactions among individuals, including high fever, following the transfusions.

"These academic records are in line with the oral testimony provided by former members of Unit 731, the army's notorious germ-warfare unit," Jin said. "The public proposal to conduct animal blood transfusion experiments on humans at the Japanese military medical conference and the publication in a widely circulated medical journal indicate that human experimentation was a transparent measure in the Japanese military medical community at the time.

"The deep involvement of the Japanese medical community in the war, conducting large-scale human experiments and bacteriological warfare under the guise of scientific research, has become part of state violence," Jin said. "It further confirms that the wartime medical crimes, primarily by Unit 731, were a large-scale, organized group crime from top to bottom in Japan.

"The museum preserves a large number of medical journals published during the war, which need further sorting and research to reveal the truth about the bacteriological warfare," Jin added. "There is also a need to continue collecting historical materials worldwide, as there is still a large amount of evidence to be uncovered."

Unit 731 functioned as the nerve center for Japan's biological and chemical warfare in China and Southeast Asia.

Historical estimates suggest that at least 3,000 people were killed in direct experiments, while more than 300,000 people across China died as a result of the biological weapons deployed by the unit.

zhouhuiying@chinadaily.com.cn