Our results highlight the urgent need for surveillance and risk assessment of these viruses, especially as we learn more about their capacity for host shifts.

Over 14 years of fieldwork in Brazil and Costa Rica, we uncovered divergent morbilliviruses in bats and non-human primates, some showing systemic infections and intriguing cross-species potential.

Our findings emphasize the need for increased surveillance in globally understudied species and regions.

It also highlights rodents as key sources of host jumps (including between animal orders).

Our evolutionary reconstructions showed that rodent-associated hepeviruses are evolutionary ancestors of hepatitis E viruses infecting humans and hoofed animals.

We uncovered genetically divergent hepeviruses in rodents, shrews, and bats by data mining and fieldwork.