Most marburgvirus infections were repeatedly associated with people visiting natural caves or mines.
Bats are good spreaders of diseases. I think they are one of the few mammals that inhabit all continents except Antarctica. I think bats co-evolved with the Angiosperm rain forests. They are riddled with viruses.
Bats are almost certainly fine, if you leave them alone.
Some years ago a registered bat handler, in Kent I think, caught rabies from a bat and he died.