Do Bats Carry Rabies?
All mammals may contract rabies, however less than 0.5% of bats actually do and typically will bite only if handled, therefore they do not pose immediate health hazards. Rabid bats often roost alone and sometimes may be observed flying during the day time colliding with objects. An infected bat will show little interest in its surroundings. Instead, it prefers to remain stationary with its eyes closed or half closed, only responding when approached. It will not seek out other animals or objects but will bite if anything should touch it. Paralytic rabies rather than the Ferocious strain of rabies is predominantly found in Mexican free-tailed bats. Unlike the Ferocious, aggressive strain associated with foxes, raccoons, dogs and other mammals, Paralytic rabies symptoms include: weakness, anorexia, hypothermia, paralysis, dehydration, irritability and depression. Sick bats will sometimes flap their wings and squeak loudly when approached. They are unlikely to attack an observer posing any bat health hazards. Most bats will die within a few days of contracting rabies. It is best advised to avoid any contact with a bat that is on the ground or allows you to approach it.
Do Bats Carry Disease?
Bats can carry Histoplasmosis, which is a fungal disease which causes respiratory problems in humans and other mammals. It is contracted by inhaling the spores of the Histoplasma capsulatum, which is a natural fungus found in soil. Like most fungi, the Histoplasma spores need warm and humid conditions to grow. Bird droppings are a primary source for the cultivation of this fungus, however, spores have also been found to grow on bat droppings especially those found in caves and buildings located in warm and humid climates. Inhalation of these spores occurs when the dry fecal matter is disturbed and becomes air-borne. The seriousness of the infection depends on the amount of spores that are inhaled and the overall health of the victim. In few cases victims have become seriously ill or have died from complications derived from the sickness. It is therefore recommended that droppings be removed when possible after a bat exclusion has been preformed to minimize the potential of contracting the disease.
How Do I Know If I Have a Bat Infestation?
- Staining: A brown or grey stain where bats are entering and exiting the roost. This is the area were exclusion nets are placed. Stains are oil based and can be difficult to remove. Bleach products and grease removers work well on the stains.
- Guano: Bat droppings underneath the roost site. The droppings are pellet like in appearance. Droppings may also stick to walls and windows. With time, the droppings will turn to dust and flush away with a good rain shower or strong wind.
- Smell: A musk like urine smell from the bats themselves and not the droppings. Most of the smell will dissipate once the bats are gone. Insulation in attics should be replaced to further eliminate the offensive odor.
- Chirping: Bats have a social roost chatter that sounds much like baby birds chirping. This chatter is audible to the human ear and is used mainly for communication amongst the colony itself or as a warning to let other bats know of impending danger.
- Visual Confirmations: Look for bats leaving the roost in the evening just around sunset or returning to the roost just before sunrise. Estimate about double the amount of bats if you count them. Not all of them will leave the roost every night. Weather may also play a factor on the size of the emergence.