Vampire bats are so known because of their appetite for blood. But in Brazil, vampire bats which have previously been thought to exclusively feed on bird blood, have been sipping on humans for supper.

Health concerns were raised after Enrico Bernard from the Federal University of Pernambuco in Recife, Brazil, and his team analysed the feces of hairy-legged vampire bats, and found human blood in the samples.

They analysed the excrement of 70 bats, and were able to extract the DNA from 15 of them. Three of these had traces of blood from humans in their faeces.