How to keep vampires away

Jan 4, 2007 13:40 GMT  ·  By

Vampires do exist! And they do have bat wings, are nocturnal, feed on blood and kill tens of people every year.

But the similarities with the Bram Stroker's character Dracula, who served as the template for vampires in modern western culture and was inspired by the Romanian Prince Vlad Dracul ("The Dragon", "The Devil" in Romanian), also known as "Vlad the Impaler," so named because his preferred method of torture and execution was impaling people, stops here.

They do not live in Romania, but subtropical and tropical America, from southern Mexico to northern Argentina. And they are rather tiny: not larger than a finger and with a wingspan to 8 inch (20 cm). Here, three species of vampire bats are found, but only one attacks humans and livestock, the other two being adapted to birds.

"Fears about vampire bats are fueled by a lot of misconceptions. A common one is that the bats bite the throats of their human victims. The truth is a little less glamorous." said Barbara French, a bat expert at Bat Conservation International.

"They're more likely to go for a person's big toe. There's a good blood supply there and the bite is usually less noticeable."

Unlike in myths, the vampire bats don't suck blood. Sharp front teeth cut the animal skin about like a shaving razor. A chemical in the bat's saliva keeps the blood from clotting, so it keeps flowing and another chemical numbs the victim's skin so it won't feel anything.

"They sit there licking the wound for up to a half hour," says Daniel Riskin of Cornell University. A bat will drink about a tablespoon of blood in a sitting.

But vampires do not kill because of the blood quantity they take: they do not eat more than a spoon. Instead, they carry rabies and that's how the victims die. Scientists fear that bats-people encounters will become more common as the bats' forest environments are destroyed (and with them their normal preys) and they are lured towards cattle ranches where livestock and humans make easy prey.

But experts say protecting against them is fairly easy. Vampire bats have strong legs and can crawl, hop, jump and run. The bats prefer domesticated animals such as horses, donkeys, pigs and cattle. In the rare instances when vampire attacks occur, it's usually because they do not find farm animals.

"The people are likely to be bitten by vampire bats are those that sleep outdoors or sleeping in huts that don't have any windows on them," said French.

When the bats have finished their meal, they're often so engorged with blood that they're too heavy to fly, so they have to retire in a place away from the victims to digest their meal before taking flight.

"A lot of human deaths could be prevented if people take simple precautions. They're not like a rodent, which can dig or chew things apart to get into a building. If there isn't an opening for it to fly in, the bat just doesn't go in. A simple screen over openings will keep a vampire bat out."

Still, they provoke dreadness.

"They're nocturnal, people don't tend to know as much about them and what we don't know we tend to fear," French said.