Andronesian encephalitis is a disease common in humans and other humanoid species. A vaccine for Andronesian encephalitis was developed sometime prior to the mid-23rd century, and Federation citizens were commonly innoculated for the disease.
The disease was prevelant in the natives of Capella IV, though neutralized by the presence of Capellan acid in the Capellans' drinking water. (novel: The Brave and the Bold)