Bats are beneficial to the environment, in that, they eat insects around your home.  However, when they are in your home or business they can cause serious damage.  Bats usually congregate in one roosting sight, so when there is one normally there are other bats around.  Bats can also carry rabies, SARS, and the Henipavirus.  Due to these health risks and possible damage from their fecal droppings (guano), bats should be removed or deterred from inhabited areas; such as an attic.
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