The U.S. Centers for Disease Control (CDC) reported that a 19-year-old migrant farm worker died one year ago in Louisiana of rabies caused by a vampire bat bite. The bat was encountered in Mexico. "This is the first reported death from a vampire bat rabies virus variant in the United States," the CDC said.
The story was reported in a number of newspapers, TV and radio outlets and blogs. Unfortunately, some of those reports were a bit misleading, especially about possible threats from vampire bats in the United States.
Bat Conservation International distributed the information to news organizations around the country in hopes of helping to set the record straight:
• According to the CDC, the victim's mother says he was bitten by a vampire bat on July 15, 2010, in the Mexican state of Michoacán, which is more than 400 miles south of the U.S./Mexico border. The only vampire bats in the United States are in zoos or research facilities. Vampires pose no direct risk for those who live in the United States.
• Like most mammals, bats can get rabies, but the vast majority of bats do not. Nonetheless, any bat that a person can approach and touch is far more likely than other bats to be infected. People should never touch a bat or any other wild animal.
• The CDC counts 32 human rabies cases in the United States since 2000, eight of them caused by exposures in other countries, usually from dogs. Most of the remaining 24 cases involved bats.
• Of more than 1,200 species of bats worldwide, only three are vampires and all are in Latin America. Two primarily feed on the blood of birds and one – the common vampire bat (Desmodus rotundus) – prefers mammals, especially livestock. Movies notwithstanding, vampire bats do not suck blood. They lap it like kittens.
• The common vampire bat uses its heat-sensors to locate where blood flows through vessels near the skin of its prey, then uses small but very sharp teeth to create modest wounds. An enzyme in the vampire's saliva keeps the blood from clotting as the bat feeds. That enzyme, by the way, is now a potent anticoagulant medication used to prevent strokes in humans.
• Vampire bats range from Mexico south through most of Central and South America. These bats require areas where winter temperatures do not fall below 50 degrees F. Research suggests, however, that if climate change continues unabated, vampires could expand into some parts of the United States decades from now.