Defoliation bacilli bomb, made between 1932 and 1933 was used by the Imperial Army

Imperial Japanese Army

-Foundation:During the Meiji Restoration, the military forces loyal to the Emperor were samurai drawn primarily from the loyalist feudal domains of Satsuma and Chōshū...

 to spread bubonic plague

Bubonic plague

Plague is a deadly infectious disease that is caused by the enterobacteria Yersinia pestis, named after the French-Swiss bacteriologist Alexandre Yersin. Primarily carried by rodents and spread to humans via fleas, the disease is notorious throughout history, due to the unrivaled scale of death...

 across unoccupied areas of China. The deployment of these lethal munitions provided the Imperial Army with the ability to launch devastating biological attacks, infecting agriculture, reservoirs, wells and populated areas with anthrax

Anthrax

Anthrax is an acute disease caused by the bacterium Bacillus anthracis. Most forms of the disease are lethal, and it affects both humans and other animals...

, plague-infected flea

Flea

Flea is the common name for insects of the order Siphonaptera which are wingless insects with mouthparts adapted for piercing skin and sucking blood...

s, typhoid, dysentery

Dysentery

Dysentery is an inflammatory disorder of the intestine, especially of the colon, that results in severe diarrhea containing mucus and/or blood in the faeces with fever and abdominal pain. If left untreated, dysentery can be fatal.There are differences between dysentery and normal bloody diarrhoea...

 and cholera

Cholera

Cholera is an infection of the small intestine that is caused by the bacterium Vibrio cholerae. The main symptoms are profuse watery diarrhea and vomiting. Transmission occurs primarily by drinking or eating water or food that has been contaminated by the diarrhea of an infected person or the feces...

. Rather than being prosecuted as war criminals, Unit 731

Unit 731

was a covert biological and chemical warfare research and development unit of the Imperial Japanese Army that undertook lethal human experimentation during the Second Sino-Japanese War and World War II. It was responsible for some of the most notorious war crimes carried out by Japanese...

 alumni became top bioweapons researchers. Shirō Ishii

Shiro Ishii

was a Japanese microbiologist and the lieutenant general of Unit 731, a biological warfare unit of the Imperial Japanese Army responsible for human experimentation and war crimes during the Second Sino-Japanese War.-Early years:...

 himself became an adviser at USAMRIID at Fort Detrick

Fort Detrick

Fort Detrick is a U.S. Army Medical Command installation located in Frederick, Maryland, USA. Historically, Fort Detrick was the center for the United States' biological weapons program ....

.