Some types of bats are key hosts for certain spillover diseases that can spread to humans, often through intermediary species like civet cats or camels.

A new paper in the journal Science Advances suggests bats in disturbed ecosystems are more likely to be infected with coronaviruses.

Human wildland encroachment raises the odds of meeting animals like bats, and wet markets bring together scores of species that normally would not interact.

But why do some bats get infected in the first place?

The research lends new support for the idea that chronic stress — caused by ecosystem disturbance, for example — can weaken animals' immune systems.

It also shows that coronaviruses are more prevalent in bats that occupy human-dominated areas, especially those involving agriculture, deforestation and energy production, including mining.

Such activities can stress bats by depriving them of key food sources and roosting areas.