Seah’s Syndrome

Seah’s syndrome is a rare medical condition affecting vampires.  Essentially, it causes a mutation of the intestinal lining whereby the vampire’s digestive system, which can usually break down and process all blood types that may be imbibed, is altered to reject all but a specific antegen blood group.  While most vampires can muddle by with standard O-type blood, and just be careful to avoid drinking any blood type which carries the rejected antegens, in extreme cases of Seah’s Syndrome the unfortunate vampiric victim can only process one specific blood group and will have a violent, often fatal reaction to the drinking of any blood which does not meet very high medical standards.

This, combined with a rising concern about blood quality and personal hygiene in general, following the discovery that vampirism did not, in fact, render immunity to certain blood-borne diseases, has naturally inhibited the lifestyle of many otherwise merrily predatory vampires, as a victim of Seah’s Syndrome, while he or she may enjoy stalking their prey, will often have to conclude their hunt with a series of personal and probing medical questions before risking even a casual drink.