Orion blood fever was a particularly virulent disease of the blood that originated from the planet Orion.

It was a devastating disease that was characterized by a high mortality rate and quick development cycle. It was first discovered among the inhabitants of Rigel VII in the mid-23rd century. (FASA RPG module: A Matter of Priorities)

An outbreak of this disease ravaged settlements, including those of the Klingons, on Rigel VII in 2270. (FASA RPG module: Star Trek IV Sourcebook Update)

By their names, origins and apparent symptoms, this disease may be the same as or related to Rigellian blood-burn fever and Rigellian fever.