The idea that bats “attack” people is a misconception fueled by fiction and misunderstanding of their natural behavior. Bats are highly beneficial, primarily insectivores that consume enormous quantities of nocturnal pests, contributing significantly to environmental health. They are generally shy and non-confrontational, actively avoiding contact with humans whenever possible.
Natural Bat Behavior vs. Aggression
Most bats found in North America are insectivorous, hunting flying insects using sophisticated echolocation. These animals are nocturnal, spending daylight hours roosting in dark, secluded spots like caves, hollow trees, or attics. Their natural instinct is to retreat from large, unfamiliar creatures, including people.
A bat may fly close to a person, especially in the evening, but this is feeding behavior, not an attack. They are pursuing small insects, such as gnats and mosquitoes, attracted to the warmth and carbon dioxide emitted by humans. Any perceived aggression from a healthy bat is exclusively a defensive response when they are cornered, accidentally handled, or feel their roost is threatened.
The notion of blood-sucking bats is linked to the three species of vampire bats, which only inhabit Central and South America. These bats make a small incision to lap blood, typically from livestock like cattle and horses. Bat species found outside of those regions, including all species native to the United States, do not feed on blood and pose no threat to humans.
Understanding the Circumstances of Human Contact
Direct human contact with a bat, which can lead to a bite, almost always occurs under specific circumstances. The most common scenario involves a person intentionally handling a bat, perhaps finding one injured or grounded and trying to “rescue” it without protective equipment. A bat in this compromised state will bite defensively when picked up.
Accidental contact typically occurs when a confused bat finds its way into a living space and is unable to exit. A sleeping person may be unaware of a bat in the room, or a child or impaired individual may not be able to report an interaction. Since bat teeth are small, a bite mark may go unnoticed, creating a serious risk for potential exposure.
A bat found on the ground or acting strangely, such as flying during the daytime, is likely sick or injured. Healthy bats rarely land on the ground because they need to drop from a height to take flight, and they naturally avoid light and noise. Interacting with a bat exhibiting abnormal behavior significantly increases the risk of a defensive bite.
The Primary Health Concern: Rabies
The primary health concern related to bat contact is the potential transmission of the rabies virus, which is fatal once symptoms develop. While it is a misconception that most bats carry the disease, less than one percent of the wild bat population is infected at any given time. Bats are the source of most human rabies cases in the United States because their small bites are often undetected.
Rabies is transmitted through saliva from an infected animal entering an open wound or mucous membrane. Because a bat’s bite mark can be small, the potential for exposure must be taken seriously, particularly in cases of unobserved contact. If a bat is found in the room with a sleeping person, an unattended child, or a person with impaired judgment, medical professionals recommend seeking immediate consultation.
If exposure is suspected and the bat is not available for testing, a course of Rabies Post-Exposure Prophylaxis (PEP) is necessary. PEP involves two components: Human Rabies Immune Globulin (HRIG), which provides immediate passive immunity, and a four-dose series of the rabies vaccine given over 14 days. Thorough washing of the wound with soap and water for 15 minutes should be the first step, followed by prompt medical attention to receive the full PEP regimen.
Coexistence and Prevention
Minimizing the risk of human-bat encounters involves preventative measures focused on exclusion and safety protocols. The most effective way to prevent bats from entering a home is by sealing all exterior openings larger than a quarter-inch. This work must be done when bats are not raising their young, typically in late fall or winter, to ensure they are not trapped inside.
If a bat is found flying indoors, the safest course of action is to close all interior doors to contain it to one room. Next, open a window or door to the outside. The bat will usually use its navigational skills to fly out on its own once it calms down and detects the open air. If the bat lands, it can be captured using a container and a piece of cardboard, but this should only be done while wearing thick leather gloves.
Under no circumstances should a bat be handled with bare hands, even if it appears docile or injured. If a bat is captured, it should be released outside away from people. However, if there was any contact, the bat should be secured for potential rabies testing. Contacting local animal control or public health officials is the best action for advice on handling the bat and determining if PEP is required.