August 12, 2011

Rabid Vampire Bat Kills Migrant Worker

A migrant farm worker from Mexico became the first person in the United States to ever die from a vampire bat bite, according to US health authorities.

The unidentified 19-year-old was bitten July 15, 2010 while sleeping in his family's home in Michoacán, Mexico, AFP is reporting. He failed to seek out medical treatment for the bat bite and instead crossed the border into the United States en route to work in a sugarcane plantation in Louisiana.

After one day working in the fields, he complained of shoulder pain, numbness in his left hand and a drooping left eye accompanied by a high fever. He died on Aug. 21, 2010.

"This case represents the first reported human death from a vampire bat rabies virus variant in the United States," said the Centers for Disease Control and Prevention (CDC) in its Morbidity and Mortality weekly report.

The unusually aggressive form of rabies had an incubation period of just 15 days, compared to the median 85 days seen in other cases of human rabies in the United States, the CDC told CBS News.

Vampire bat populations are currently confined to Latin America, but climate changes could be forcing their populations northward, leading to more cases of human infection in the southern United States, the CDC warned.

The agency continued, "Expansion of vampire bats into the United States likely would lead to increased bat exposures to both humans and animals (including domestic livestock and wildlife species) and substantially alter rabies virus dynamics and ecology in the southern United States."

The US has documented a total of only 32 cases of human rabies, primarily from a canine rabies variant, since the year 2000. Eight of these cases were acquired abroad, two of the cases originated in Mexico.

Vampire bats are bloodsucking nocturnal mammals that are typically found in Mexico, Brazil, Chile and Argentina. They usually feed on sleeping wildlife and livestock but have been known to bite people also.


Image Caption: The vampire bat, Desmodus rotundus, must find a blood meal every 1-2 days to survive. Razor sharp teeth and infrared-sensing "pit organs" surrounding its nose help the bat achieve this goal. Credit: Dr. Pascual Soriano


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