Sci-Tech

Vampire bats now snacking on human blood

Garlic won't save you. Some vampire bats in Brazil surprised scientists by adding human blood to their diets.

This hairy-legged vampire bat was captured in Mexico.

Gerry Carter

Just when you thought vampires nibbling on people was something that only existed in the realm of fiction, scientists have discovered some real vampiric activity in Brazil.

Researchers from the Universidade Federal de Pernambuco found evidence of human-blood consumption in hairy-legged vampire bats (Diphylla ecaudata).

These bats are known for feeding on bird blood, so the presence of human blood as seen in a DNA analysis of bat feces was a surprise. "This species isn't adapted to feed on the blood of mammals," researcher Enrico Bernard told New Scientist.

The scientists published a study on the find in December in the journal Acta Chiropterologica with the delightful title "What is for Dinner? First Report of Human Blood in the Diet of the Hairy-Legged Vampire Bat Diphylla ecaudata."

The research team was looking into how the species would behave with a scarcity of its natural prey and an increase in domestic animals in the area.

While they collected 70 guano samples, only 15 of those provided DNA and 3 out of that smaller batch showed traces of human blood.

The analysis also turned up chicken blood. "Our results suggest that the diet of D. ecaudata is more flexible than expected. The record of humans as prey and the absence of blood from native species may reflect a low availability of wild birds in the study site, reinforcing the impact of human activities on local ecological processes," the paper notes.

The findings raise concerns about the transmission of diseases, including rabies. According to New Scientist, Bernard and his team are now looking into how the bats access humans at night, whether it's by finding people sleeping outside or by entering homes.

At least the whole fictional issue with vampires turning humans into new vampires won't be a problem.

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