Costas Efthimiou is a professor of physics at the University of Central Florida, who apparently spends his time debunking myths and legends. Judging from his website, he’s also a fan of web aesthetics circa 1995. I’d post a screengrab, but it could never capture the untamed beauty of an animated “Under Construction” gif.

Anyway, Efthimiou has deduced the vampires are a mathematical impossibility with the following simple logic: if a vampire bit once a month, and all victims became vampires, the vampire population would increase exponentially until it wiped out the human population.

Efthimiou states that if the first vampire appeared on January 1st 1600, when the estimated human population was 536,870,911, everyone would be vampires in just “two and a half years”.

It seems pretty straightforward, after all, 1 x 2^{29} is… heywaitjustagoddamminute: 536,870,912?! That’s just one more than Efthimiou’s absurdly precise population estimate for the year 1600. It’s almost as if he made up that population estimate to neatly fit his maths. Of course, with a reproduction rate of, ooh, let’s say 1%, the human population would have increased in that time by roughly 12.4 million, an aberration neatly tied up by Efthimiou’s requisite 30th month. Even starting with a human population of 6.75 billion, it wouldn’t take long for us all to be turned into bloodsucking nightcrawlers.

Of course, there are a lot of assumptions at play here – that vampires feed monthly, that they only attack humans, that they don’t die, that there is no immunity, that vampires are perfect hunters (humans are going to be a lot harder to find toward those end days). What I’m saying is that this is a good idea, but Efthimiou hasn’t geeked out nearly as much as he could have. After all, there’s a whole field of vector biology out there.

I’m sure we can come up with something a little more comprehensive. Your suggestions for factors to be taken into account when calculating the spread of vampires below please. Enough good comments and I’ll plot some lovely graphs and post them.

Finally, it’s worth pointing out that Efthimiou’s conjecture doesn’t rule out the possibility of vampires – just that the outbreak hasn’t happened yet. For all we know, Nosferatu might be tucking into his first victim tonight. We’ll know for sure in two and a half years…