Our Expert Voices conversation on emerging diseases.

The vast majority of infectious diseases that plague us come from animals, in particular from wild mammals. Think SARS, Ebola, Zika, and HIV – the deadliest zoonoses of them all.

It's urgent that we better understand where, from what species, and how these diseases are jumping into people. This almost always involves people meddling with the environment – in which viruses are part of the delicate balance. Rampant deforestation, wildlife trade, urbanization, and globalization are increasing our chances, year-by-year, of the next 'big one' making the jump.

Mathematical models represent a powerful tool to tease out the underlying causes of disease emergence, and prioritize wildlife species likely to harbor the next zoonoses. In recent work, we found that bats carry more zoonotic viruses than other mammals and that a large number of the "missing zoonoses" carried by these mammals may be in South America. In East Africa, hoofed animals may be harboring more zoonotic viruses and along the equator there are clusters of primate-borne viruses.

Bottom line: There are over 5,000 mammal species on the planet and likely many thousands of undiscovered viruses that could infect us. It's urgent we develop new analytical tools to sort through the noise and prioritize disease surveillance efforts on the ground to find and characterize as-yet-undiscovered zoonoses before they cause the next pandemic.

Other voices in the conversation:Thumbi Mwangi, veterinarian, Washington State University: Control small diseases to be ready for big onesAnne Rimoin, epidemiologist, UCLA: Watch where people and animals interactJustin Lessler, epidemiologist, Johns Hopkins University: It's not where a virus comes from but how it becomes contagious