Bat Bugs: What to Know

Medically Reviewed by Jabeen Begum, MD on January 13, 2023
5 min read

Finding an infestation of tiny, biting bugs in your house is always cause for alarm. You might immediately assume that you have bed bugs, but you may have a lesser-known relative of the bed bug: the bat bug. These pests come into houses when wild bats roost in the attic or behind walls. To get rid of them, you'll need to eliminate the bugs and make sure the bats that brought them can't get back into your house.

Bat bugs are close relatives of bed bugs. Both pests fall into the family Cimicidae, which contains 22 varieties of insects. Twelve varieties of Cimicidae are associated with bats, whereas the others prefer to feed on birds or other mammals.

Bat bugs and bed bugs look nearly identical to the naked eye. They're both small, brown, oval-shaped bugs. They have stubby, non-functional wings and beak-like mouthparts. They're approximately 1/4 to 3/8 of an inch long when they're fully grown. Bat bugs have longer fringe hairs on the upper part of their thorax than bed bugs, but they can only be differentiated under a microscope.

Bat bugs, like bed bugs, feed on blood, but their preferred host is bats or birds instead of humans. Nevertheless, they will bite humans if there are no bats available. Adult bat bugs can live for up to a year without a blood meal, but the lack of blood stunts development early in the bat bug life cycle. In addition, female bat bugs need a blood meal to produce eggs.

Female bat bugs lay eggs on rough surfaces or cracks close to their living space. The eggs hatch within one to two weeks, and the nymphs emerge. Nymphs require a blood meal to molt. Bat bugs mature to adulthood within about six weeks, depending on the availability of blood meals.

Bat bugs are found all over the world. The most common type of bat bug in the United States is the Eastern bat bug (Cimex adjunctus). They have been found in eastern and Midwestern states.

Bat bugs prefer to cluster in spaces where bats roost. They hide in cracks and crevices around any space where bats are found, including in buildings. They don't live on the bodies of bats all the time. They prefer to feed on an animal and then retreat to their own space.

Bat bugs mainly cluster around their preferred food source to eat and reproduce. Bat bugs can't fly on their own, but they can cling to bats as they fly out of the roost. Bat bugs spread by hitching a ride on a bat and setting up a new habitat after leaving the animal's body. Even if the bats leave their roost, the bugs can stay alive without bat blood. Adults can stay alive without blood or feed on other mammals and birds.

The first sign of a bat bug infestation may be bites on your skin. If the bugs have migrated into the living areas of your home, they might bite you or your family members. The bites can cause itchy welts on your skin.

You may also be able to see the bat bugs moving around your home. They usually live in cracks or crevices on windows or walls. They can settle into furniture as well.

Bat bugs come into buildings with bats. Bats may roost in the attic, chimney, or behind the walls of a building. When this happens, bat bugs can flourish around the bats' space. Typically, they stay close to the bats and don't bother humans. But if bats leave their roost, the bugs will go looking for food. That's when they can migrate throughout a building and encounter humans.

Bat bugs are not dangerous to humans or animals. They're not known to transmit diseases. Their bites can be uncomfortable and cause itchy, raised patches similar to other types of insect bites. This happens because many people are allergic to an element in their saliva, so they react when they're exposed to it.

If you're bitten by a bat bug, you can manage the bites with home care. Gently wash the area with soap and water, then apply a cool compress or ice pack to the bite to soothe the irritation. You can use an over-the-counter anti-itch cream to reduce the discomfort from the bite. You can also try taking an over-the-counter anti-histamine if topical creams don't help.

If you have an extreme reaction to any type of insect bite — for example, if your face, mouth, and throat swell up or if you have difficulty breathing — call 911. Serious allergic reactions can be life threatening and require immediate medical attention.

Getting rid of bat bugs means both controlling the infestation of bugs and eliminating the bats from your home. If you only eliminate the bugs, you risk a repeat infestation if the bats return to their roosting area.

Note that certain species of bats are protected because of their role in the ecosystem, so it's not legal to kill them. You should speak with a professional pest removal service or local wildlife management agencies about getting bats out of a building and keeping them out.

Once all the bats have been removed, you'll need to seal your house to make sure they don't come back. Locate the entrances the bats are using to get into the building, and secure them once the bats are out. You should also seal any additional cracks and cover open vents so the bats don't find different ways back into the building. 

After removing the bats, you can address the bat bugs. You can use an insecticide treatment, such as so-called bomb treatments, to kill any bugs in your home. Be sure to follow the instructions to protect the safety of the people and pets in your home. You can follow up by using insecticides to spot-treat cracks or crevices where bugs may be hiding.

Professional pest removal services can also treat your house and remove the bugs. They may suggest a schedule of follow-up services to make sure all the pests are eliminated. 

After treating the house for bat bugs, you can help remove any remaining pests with frequent cleaning. Vacuuming, dusting, and laundering clothing and linens will remove any lingering bugs.