Dear Vika: I was an epidemiologist in MA Public Health Division of Infectious Diseases in
early 1950s when bat rabies was first discovered in US. At that time it was thought
that the few cases of human rabies in people who explored caves where vampire bats
were numerous might be caused by aerosols of rabies virus. That risk has indeed turned
out to be very small. I found one site that said only two cases :
"two human deaths probably due to nonbite aerosol transmission".
If it has been documented in one cave in Texas, it seems quite possible it could
occur in other similar caves. I'm glad it is so rare.