The next deadly disease to jump from bats to humans is most likely to emerge in Sub-Saharan Africa, according to an article published today in The American Naturalist. Bats are the suspected source of several deadly viruses that have infected humans in recent years, like Ebola or severe acute respiratory syndrome (SARS), and they are likely to harbor more. To find out what drives such spillover events, researchers went through more than 100 years worth of records to identify viruses carried by both humans and bats and drew up a map (pictured). The number of shared viruses increases from green to dark red. They identified Sub-Saharan Africa as the region with the biggest overlap between human and bat viruses with a maximum of 16 viruses in some regions. They then tried to model the factors driving this pattern. Their conclusion: The more bat species a region harbors, the higher the risk of a virus spilling over, but bushmeat hunting and high population densities also contribute, by creating opportunities for the animals to transmit their diseases to humans.