According to an article by the Associated Press:
Efthimiou takes out the calculator to prove that if a vampire sucked one person's blood each month -- turning each victim into an equally hungry vampire -- after a couple of years there would be no people left, just vampires. He started his calculations with just one vampire and 537 million humans on Jan. 1, 1600 and shows that the human population would be down to zero by July 1602.Of course, the problem with that calculation is that it assumes that vampires need to suck the blood of a different person each month. In Bram Stoker's Dracula, the Count feeds on poor Lucy multiple times. In fact, red blood cells only live about four months, and must be constantly replaced. That's why you can safely donate blood every eight weeks or so. So for vampires to be "realistic", all they need to do is feed off the same people multiple times.
Efthimiou points out that the best known example of zombification, Wilfred Doricent, was actually a case of paralysis due to tetrodotoxin poisoning. Tetrodotoxin is found in the liver of pufferfish, and is the chemical that makes Japanese fugu potentially lethal. The poison causes paralysis while the victim remains fully conscious. Death comes eventually by asphyxiation. People can "wake up" from apparent death after a relatively mild case of tetrodotoxin poisoning. An ex-voodoo priest has apparently confirmed that zombification indeed involves a potion which contains extract from the liver of a Hatian pufferfish.
Other studies have noted that some people considered zombies by their families really have brain damage or suffer from mental disorders such as catatonic schizophrenia.
So while a science-based story could certainly include "vampires" and "zombies", they would have to be different than the way they are depicted in popular horror movies.
- Efthimiou & Gandhi "Ghosts, Vampires and Zombies" (2006) (pdf file from arXiv.org)
- Download Dracula as a pdf from Google Books.
- Read Dracula as in diary form at Dracula Blogged
- SciFan's list of science fiction and fantasy books and stories with the theme of Vampires or Vampirism
- Donate blood via the Red Cross, or find another blood bank.
- Dr. Karl radio program on zombies
- Interview with Wade Davis, the ethnobotanist who first wrote about Hatian zombie rituals. You can get Davis' book, The SERPENT AND THE RAINBOW from Amazon.com.
- Night of the Living Dead (1968) is now in the public domain. Download it at the Internet Archive.
- SciFan's list of science fiction and fantasy books and stories with the theme of the Undead (including Zombies, Ghouls and Mummies).