5 Types of Flies That Might Try to Bite You This Summer
Are fly bites dangerous?
Flies dive-bomb your face, they march across your food, and they can bite. Annoying? Sure. Painful? Sometimes. But are fly bites dangerous? The comforting answer: Rarely.
“Flies are not typically harmful in the United States,” says Rosmarie Kelly, PhD, a public health entomologist with the Georgia Department of Public Health in Atlanta.
Flies generally aren't responsible for passing on diseases, at least not in the U.S., although their bites can hurt and some people have more serious allergic reactions to their saliva.
Here are five common U.S. flies and what their bites can–and can’t–do to you.
Types of fly bites: Horse fly bites
Horse flies, of course, congregate on and near horses (and other large animals). They are attracted to movement and carbon dioxide, and they like water and teem in hot, humid states like Florida.
Horse flies don’t spread disease to humans, but if you get bitten by one, you’ll know it.
“They have slicing and cutting mouth parts,” says Kelly. “They have little razors that make a shallow groove in the skin and lap up blood.”
You may get a red bump or rash that itches. This type of reaction usually doesn't need treatment, although an antihistamine cream may soothe some of the sting, says Kelly.
Depending on how sensitive you are to a horse fly’s saliva, you may also get dizzy and weak, start wheezing, or swell in different parts of your body. This is an allergic reaction, and it does need treatment.
See a doctor if you have any allergic symptoms or if you see signs of infection like pus and swelling. Some horse fly bites can lead to cellulitis, a bacterial infection.
Sand fly bites
Sand flies are typically found in southern U.S. states, including Florida, Louisiana, Arkansas, Tennessee, and North and South Carolina.
Sand fly bites can cause small red bumps and blisters that may itch and swell. Antiseptic and soothing lotions will help ease itching and prevent infections from developing.
In rare cases, sand flies can transmit a parasitic disease called leishmaniasis, which can cause skin ulcers, shown above. These usually heal within a year, but they can leave you with scarring.
U.S. troops in the Middle East often have trouble dealing with sand flies, says James Diaz, MD, DrPH, professor and director of the environmental and occupational health sciences program at Louisiana State University School of Public Health.
Deer fly bites
Deer flies are common in the U.S., especially in the Southwest. These critters particularly like swamps, lakes, and other bodies of water. Like horse flies, they’re attracted to movement, carbon dioxide, and warmth.
Deer flies have the same razor-sharp mouths as horse flies and can inflict quite a bit of pain and often draw blood. Antihistamines, along with antiseptic and soothing lotions, are probably enough to tame their bites.
A few people have allergic reactions to deer fly saliva, which could lead to symptoms like hives or wheezing. Deer flies also occasionally transmit or “rabbit fever,” a bacterial infection that is usually treated with antibiotics.
Black fly bites
Black flies, also sometimes called buffalo gnats, are very common in the U.S. and, although they bite, they don’t transmit diseases in this country. They appear in the late spring and early summer, especially along creeks and rivers.
Black fly bites result in red bumps that itch and often swell. These critters are especially fond of your head, face, and the back of your neck. Some people have severe allergic reactions to black fly bites, which need to be treated by a medical professional.
If one black fly takes a nibble, it can hurt. But if hordes swoop down and bite you, you can get severely injured.
Some people react with a collection of symptoms known as “black fly fever,” which can involve headache, nausea, fever, and swollen lymph nodes.
To get our top stories delivered to your inbox, sign up for the
Biting midges or gnat bites
These pesky insects are a nuisance particularly in hot and humid areas. Often you’ll feel the bite (they hurt) without ever seeing the culprit–hence their “no-see-ums” nickname. Biting midges are most likely to deliver their trademark burning sting at dusk and dawn.
Midge or gnat bites look a lot like mosquito bites: small, red, itchy lumps or sometimes a red welt or blister. The bugs don’t spread diseases to humans, though they can infect livestock.