The blood of young mice has been shown to reverse certain symptoms of aging in the bodies of elderly mice:Young Blood
The process isn’t quite so simple as a blood transfusion. The circulatory systems of the paired animals were surgically conjoined. Still, here’s a scientific rationale for vampirism.
Vampires could be people who either have the innate ability to process the blood components that make the mouse experiment work or, thanks to futuristic science, have undergone genetic manipulation to grant them that ability.
The experiment reminds me of the short story “Good Lady Ducayne” by Mary Braddon, published in 1896. An innocent young woman takes a job as companion to the rich old lady of the title. Previous companions haven’t lasted long; they all mysteriously wasted away. A doctor who becomes romantically involved with the heroine discovers Lady Ducayne’s secret. An unscrupulous physician in her pay has been transfusing her companions’ blood into her veins to maintain her vitality. In 1896, this tale was purely speculative fiction, because consistently successful blood transfusion hadn’t yet been achieved (blood types not having been discovered). The possibility seems to have been “in the air,” since Lucy in DRACULA receives four transfusions. Fred Saberhagen’s THE DRACULA TAPE suggests that incompatible blood types, not the Count’s visits, actually caused her death. To readers of later decades, the notion that a blood transfusion could bestow youthful vigor on the recipient sounded as pseudoscientific as Van Helsing’s belief that the blood of strong, brave men (regardless of more tangible physiological factors) could save a vampire’s victim—until now. Science sometimes validates fiction’s crazy ideas!
Margaret L. CarterCarter's Crypt