The utilization of infectious agents, referred to as bioweapons, including substances like defoliants and neurotoxins, to cause death in living things during warfare is known as biological warfare. In the time of the Clone Wars, Doctor Nuvo Vindi reconstructed and altered the previously eliminated Blue Shadow Virus disease while researching biological weapons that could defeat Jedi. Later, during the same war, Morseerian scientists attempted to create an infectious agent to use against the Grand Army of the Republic's clone troopers.
Following the Battle of Ringo Vinda, clone trooper Tup killed Jedi General Tiplar without any clear motivation, which baffled the Jedi and fellow clones. Tiplar's sister Tiplee and General Anakin Skywalker questioned whether his actions might have been due to a rumored anti-clone virus that the Separatists were supposedly working on. During the Galactic Civil War, the Galactic Empire made use of the planet Coyerti as a location to experiment with and create biological weapons.