[Name] Drafa Plague [Source] Babylon 5 [Symptoms] 
Neutralizes chemicals in the synaptic gap, thus inhibiting nerve signals from the brain to the rest of the body. Without such signals from the brain as a result of the signals being blocked, the organs lose their ability to function correctly. For those that which used specialized cells to produce neurotransmitters, the disease is 100% contagious, and if left untreated 100% terminal. Fortunately for most of the other sentient races, their lack of such specialized neurotransmitter cells render them immune to the disease. It bears a stigma among the Markab (who were wiped out by it) similar to HIV/AIDS among humans, as a disease only caught by those considered sinful, immoral or unclean by Markab standards, and a punishment by their gods for committing such acts, and was named after an island on their homeworld where people were wiped out by the disease, an island noted in Markab history for its decadence and immorality.