Presumably it's been there for a long time and we just noticed.
As a previous commenter noted, rats are an invasive species in the expanding human/wildland interface. So they will be encountering novel bat viruses.
There may be other existing bat to human transmission paths, but maybe not....
We just noticed bat snatching. I doubt it's new discovery that rats also eat bats whenever the opportunity comes knocking.
Also: Bats -> rats -> (house) cats -> humans.
Presumably it's been there for a long time and we just noticed.