Rabies is feared for its lethality. It's known to be nearly fatal if an infected person shows clinical signs. And while 99% human rabies cases can be traced back to transmission by a dog bite, bats are the main source of infection in the Americas.
Scientists are thus surprised that they have found human blood in a bat species previously thought to only feed on birds. Human blood DNA was found in 3/15 samples of bat poo from a species of South American hairy-legged vampire bat, and has prompted concerns of another vector capable of spreading the rabies disease.
It is thought that human activity has allowed the adaptation of this vampire bat species to humans, especially since bird blood composition is vastly different from human blood composition. As logging continues in Brazilian forests, birds are being driven out of the area, forcing the vampire bats to find new sources of food.
Fear not, a rabies vaccine and post-exposure treatment with immunoglobulins are available. Do be vigilant to get your vaccine if you plan to go bat-sighting.
Original scientific article: http://dx.doi.org/10.3161/15081109ACC2016.18.2.017
More on Rabies: http://www.who.int/mediacentre/factsheets/fs099/en/
-- Sharon Kam