Sir, - Margaret Ward's account in Science Today (The Irish Times, October 26th) gives an enlightening account of Dr Alonso's article on furious rabies as a possible scientific explanation of vampirism.
However, another medical disorder may well have been in Bram Stoker's mind when he created Dracula. His brother, Sir Thornley Stoker, an eminent surgeon in the Richmond Hospital, greatly influenced Bram's writing; in particular, some medical textbooks in his possession relating to rare and unusual diseases certainly could have given a viable explanation of the concept of vampirism.
One such disease, a rare hereditary blood disorder called porphyria, is alleged to have plagued the royal houses of Stuart, Hanover and Prussia. Cluster groups still occur in central Europe today in greater frequency than in other parts of the world. A victim of porphyria cannot produce heme, a vital component of the red blood cell. Being hereditary, the disorder could easily have been misinterpreted as contagious in medieval times. Sufferers would have extreme sensitivity to light, their delicate skin breaking down in contact with ultraviolet rays. Hence victims would fear the sun, remaining indoors and going out only at night-time. They would be pale, and obviously anaemic, and before modern treatments it was believed that the ingestion of fresh blood was necessary to replace lost iron. Their lips and gums often receded, making the incisors prominent. They suffer personality changes, in particular psychiatric manifestations, becoming excitable, manic, and in rare cases hypersexual. In extreme cases complete paralysis occurred with a cataleptic-like state in which the person appeared to be dead, only later to recover either in a vault or a coffin. Significantly, garlic causes a porphyria sufferer to worsen.
The above does not explain all the symptoms a vampire is alleged to have but could provide us with an insight into what Bram Stoker may have seen in his brother's books. - Yours, etc., Dr Denis Eustace,
Swords Road,
Whitehall,
Dublin 9.