Which flies bite: signs and symptoms

Flies are a nuisance. You have probably seen flies both indoors and outdoors, buzzing around and landing on kitchen counters and right on your food. There’s a good chance you also already know flies are unsanitary because they tend to land on garbage, feces and other dirty objects. This causes the flies to pick up bacteria, which they can transfer to food and cooking surfaces which can create health risks for you. But did you know some fly species bite?

Several species of fly need blood in order to reproduce and will gladly bite humans to get this blood. These flies need the proteins to create eggs. When it comes to pest control, Western Exterminator pest control technicians are experts in most fly species, including biting flies. We can help you get rid of flies in your home and around your property. Contact your local Western Exterminator office today.

Why do flies bite?

Flies do not need to consume blood in order to live. So, why do flies bite in the first place? Most species of flies prefer other food sources, such as nectar from plants. However, for reproduction, flies need the proteins found in animal blood in order to mate and produce eggs.

Flies have special mouthparts like mosquitoes, fleas, ticks and bed bugs, allowing them to pierce the skin and access blood vessels. They also inject anticoagulants contained within their saliva, which allows the blood to flow freely into their bodies.

Why do flies bite humans?

Why do flies bite humans? As noted above, biting flies like horseflies or black flies need the protein in blood to produce eggs and complete their life cycle. Human skin offers easy access to blood vessels, especially in warm weather when more skin is exposed. Some people may also be more attractive to flies due to body heat, sweat, or scent.

If you’re experiencing biting flies on your property, our fly pest control services can help address the problem.

Are fly bites dangerous?

Fly bites do carry some potential health risks. Some viruses and bacteria can be carried by the insects in their systems, which can be transmitted to humans and animals via their saliva. Fortunately, the biggest risks tend to affect other animals. Horse flies, for example, can carry anthrax, which they can transmit to sheep or cattle. However, some species of biting flies can transmit diseases such as:

• Sand fly fever
• Bartonellosis
• Leishmaniasis
• Tularemia

The bites of black flies, stable flies, and horse flies can be painful to humans, and those sensitive to insect bites and stings can experience allergic reactions.

What happens when a fly bites you?

It can depend on the species, but most bites involve a sharp, painful sting. Flies slice or pierce the skin to draw blood, leaving behind a red bump, rash, or welt. The bite area may become itchy, swollen, or even bruised. In rare cases, bites may lead to infection or a severe allergic reaction, especially if the fly introduces bacteria into the site of the bite.

Some flies can spread illnesses like rabbit fever (Tularemia) or affect the lymph nodes, though this is uncommon. If you notice symptoms like fever, wheezing, or spreading redness around the affected area, speak with a healthcare provider. 

While people often find that treating fly bites with cold packs and/or antihistamine is sufficient, you should always seek medical attention if symptoms get worse.

Which flies bite and what do the fly bites look like?

Fly bites may look different depending on the species involved. Since each species of fly is a little different, it can depend on where you are and which fly has chosen you for its blood meal.

• Horse flies - These are large, dark, flies and their bites are painful. Their mouths have nasty cutting and slicing parts, described as tiny razor blades which cut through the skin down to the blood vessels. These bites leave behind red bumps or rashes.
• Sand flies - The bites of these much smaller flies are a little more typical of an insect bite. They usually appear as red bumps, much like mosquito bites. However, you are likely to find a large cluster on your ankles, legs and feet.
• Deer flies - These flying pests are in the same family as horse flies and have the same cutting, slicing, razor-like mouthparts. There’s a good chance you’ll feel the bite as it happens. You’ll see blood and end up with red welts and rashes.
• Black flies - The bite from these flies are like sand flies: small, red, bumps. These flies show up during the spring and summer and love to be near water like lakes, creeks and rivers.
• Gnats and biting midges - These are tiny insects which will bite when you venture into hot, humid areas. These bites often hurt and you’ll feel them, but you probably cannot see the tiny culprit. This is why these flies are sometimes referred to as “no-see-ums.” Their bites also strongly resemble mosquito bites and appear as red bumps.

Why do flies bite before it rains?

So why do flies bite before it rains? The simple answer is that fly behavior changes with the weather. When the air gets more humid or pressure drops, flies become more active. These conditions often signal rain. Female flies may bite more often to feed before sheltering from the storm.

In some parts of the United States, this can lead to a noticeable rise in fly bites right before bad weather hits. While this behavior isn’t fully understood, experts believe weather shifts may trigger instinctive feeding. 

Using light repellents like picaridin can help reduce bites, but for longer-term protection, speak to one of our pest control experts about fly management at your home or business.

Western Exterminator gets rid of biting flies

If you are outside enjoying your yard and find yourself the victim of fly bites, don’t try to get rid of them on your own. Flies can lay eggs in numerous places and if you miss a few, you can just end up with a re-infestation of biting flies. Western Exterminator technicians can track down where the flies are coming from, particularly if you are finding them indoors, and offer treatments to get rid of the infestation.

Western Exterminator offers residential and commercial pest control services designed to help prevent return infestations around your home or business.

Contact your local Western Exterminator office today and discuss the fly problems you are experiencing. We’ll help you get on the path toward eliminating flies and so you can enjoy your property without worrying about bites.