A combination of genetics, environmental triggers, and learned behaviors influence the development and maintenance of phobias.
A negative past experience is very often the underlying cause of chiroptophobia. For instance, a young child startled by the sudden and noisy appearance of a flock of bats might cause the development of this phobia.
Some bats carry rabies, and people scratched or bitten while trying to capture a trapped or injured bat may encounter the disease and thereby develop an aversion to the animal. Only one in about 1,000 bats carry rabies but there is no way to identify which bats are carriers; the popular impression is that all bats are. Although bats are neither dangerous nor aggressive to humans, their leathery wings, and beady eyes nevertheless put off most people.
The most common cause of chiroptophobia is however popular lore. A bat entering the house forewarned impending death in medieval Europe. Medieval Europe also promoted the image of bats flying in the night with the Devil, and the graphical representation of the Devil in those days featured bats wings. This image struck and has transmitted through the ages. Bats, through no fault of their own have been associated with evil and undesirable characters such as Count Dracula, vampires, and the like.
Another popular piece of folklore that leads to fear and aversion of bats is the myth that a bat entangles in the long hairs of women, and that the only way to get rid of it is to chop off the hair.
Such deep-rooted prejudices have found their way into modern life and society also, with the most popular example being Halloween. Modern day stories and films often transform vampires into bats, and Batman, the famous DC Comics character choose to emulate bats to strike fear into the hearts of criminals.