All bats drink blood. The little brown bat is a harmless insect eater. When bats occupy a human dwelling, the smell, sight, and sounds from the colony are sometimes considered a nuisance. Bats do not gnaw wood, build nests, or cause damage to buildings. Histoplasmosis, a fungal respiratory disease associated with birds and other animals, may be found in the guano where bats roost.
Infection can occur when the fungus is inhaled while collecting dry bat droppings.
If droppings accumulate in lofts, sheets can be placed to collect them for use as fertilizer. Care should be taken to wear a protective mask when collecting bat droppings. Although very serious, this illness is rarely fatal. Rabies in bats is very uncommon however the few cases of rabies reported in the Atlantic provinces are mostly attributed to bats. In 1989 one case of rabies in a fox on the south coast of Newfoundland was thought to be due to contact with a rabid bat.