Sébastien Puechmaille

Visits to bat caves may up risk of spreading infectious diseases in West Africa

In West Africa, humans have eaten rats, monkeys, and bats for millennia—especially when other food sources are scarce. Yet this “bush meat” can make people sick, particularly when what’s for dinner is smoked bat. The winged creatures host more than 65 known human pathogens, including the Ebola virus, coronavirus (which causes SARS), and rabies, among others. Little is known, however, about how the various diseases, known as zoonoses, jump from bats to people, in part because how often, how, and why the two interact with each other is not well understood. Now, a new study suggests that they come in contact with one another frequently and for a variety of reasons. In three rural towns in Ghana between 2011 and 2012, researchers surveyed about 1270 people to learn more about their interactions with bats. They found that about 65% of respondents reported some contact with the creatures. About 37% said they’d been bitten or scratched by the animals or exposed to their urine—all possible routes of exposure to the viruses. And nearly half said they visited bat caves frequently, for reasons ranging from hunting to conducting religious activities to fetching water to “recreation.” Only 17% said they came into contact with bats in their normal living or work environments. About 45% of those surveyed reported eating bats, mainly sourced directly from the caves where bats roosted in drowsy clusters, the researchers report online today in Emerging Infectious Diseases. The researchers also note that roasted or fried bats (pictured) were widely observed in the local markets. Eating properly cooked or smoked meat isn’t thought to spread the pathogens. But hunters and those who prepare the raw meat for consumption or sale—and come into direct contact with the animal’s blood and fluids—are at risk. Continued efforts to understand the behaviors that bring humans into contact with bat-borne zoonotic pathogens could provide insight into stemming future outbreaks, the researchers say.