Hundreds of years ago, before there were scientific explanations for every day occurrences (like diseases) people would explain them with superstitions and magic. If you sneezed, it was because you were possessed, if you were too hairy it was because you were a werewolf, if your young children were naughty it was because of the fairies …etc. Nowadays, we have completely logical explanations for these things. Keeping this in mind, you can understand why countless historians and doctors have tried to explain the birth of the vampire myth.
It is said that the vampire myth originated because people back then didn’t have the knowledge to explain things like rabies or porphyria. Those two are often attributed to vampirism, but we have yet another disease to add to the mix – tuberculosis.
Tuberculosis, a common and usually deadly infectious disease, is yet another sickness that may have something to do with vampirism. You see, when one family member died from it, the other members of the household that were infected would slowly lose their health as well. People believed that this was caused by the first victim draining the life from their remaining family members.
Additionally, people who had tuberculosis often exhibited symptoms similar to what people considered to be vampire-like traits. Some tuberculosis symptoms included red, swollen eyes (which made them sensitive to bright light), pale skin, very low body heat, a weak heartbeat, and coughing up blood. As you can see, that would give any uneducated person in the Middle Ages reason to believe the victim was really a vampire. If you add in the fact that some may have believed that drinking blood was the only way to replenish the blood they coughed up, well, then you definitely have all the components for a good vampire legend.
Personally, I believe it was tuberculosis and other diseases that were responsible for the vampire myth growing so large back then. But what do you guys think?