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Black Fly Bites: Are They Dangerous to Dogs?

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By Nicole Cosgrove

black fly macro

Black flies are common flies that show up in the warmer seasons, flying around and often annoying people and animals alike. They’re not dangerous to you and your dog, but they can ruin a nice day if there are large groups of them around. Thankfully, black flies are pretty harmless, and their bites rarely need medical treatment beyond home remedies.

Dogs and other animals are no exception to black fly bites, leaving behind itchy bite spots. The bites themselves look scary, but they are easy to treat at home. Regardless, it’s important to monitor any fly bites to prevent any infection or complication while healing. If you think your dog has black fly bites, read on to identify and treat them properly:

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What Do Black Fly Bites Look Like?

Black fly bites have a very distinct look, which makes it easier to identify on your dog. Black fly bites have a red circle or ring around the bite, which resembles a red dot or bullseye. The red bites are sometimes flat and sometimes raised in the center. It can be a bit itchy, depending on the size and the number of bites in general. Black flies often bite softer skin, so you’ll often find bites on your dog’s belly, thighs, and ears.

Except for some mild itching or irritation, black fly bites are harmless and will go away on their own. They look considerably worse than they feel, so there’s no need to panic and rush to an animal hospital. If your dog has a lot of bite marks, keep an eye on them to make sure they don’t develop a bacterial infection.

Black Fly Bite Symptoms:

  • Red spot or ring
  • Slightly swollen bite
  • Very mild itching

Are Black Fly Bites Dangerous to My Dog? Should I Call the Vet?

No, black fly bites are not dangerous to your dog. The exception is an infection, which can happen with any type of animal or insect bite. The only other exception is an allergic reaction to the bite, which is rare but not impossible. If the bites turn infectious or don’t heal in a few days, contact your veterinarian for treatment options. If your dog is having a severe allergic reaction, go to an animal hospital immediately.

Signs and Symptoms of Allergic Reactions:

  • Anaphylactic shock
  • Wheezing or shortness of breath
  • Swelling of the face, gums, eyes, mouth
  • Hives/rash
  • Difficulty moving/walking
  • Excessive drooling
  • Diarrhea/Severe indigestion
Drooling sleepy Irish Setter_Reddogs_shutterstock
Image Credit: Reddogs, Shutterstock

How to Treat Black Fly Bites

Thankfully, black fly bites are a breeze to treat at home. If your dog seems bothered by the black fly bites, there are a few ways to help relieve the itching and discomfort:

  • Wash the dog bites with mild soap diluted with warm water, pat it dry.
  • Add a small amount of Neosporin to the bites. Let the Neosporin dry and prevent your dog from licking it.
  • Wrap an ice pack in paper towels and apply to your dog’s fly bites to relieve any swelling.

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About Black Flies

What are Black Flies?

Black flies are a common type of fly in many parts of the world, classified as a member of the Simuliinae family. Also known as buffalo gnats, black flies are a nuisance in the spring and summer. They feed off of blood from both humans and animals, often biting near the head, ears, belly, and behind the knees. Although annoying, the bites from black flies are rarely a cause for concern.

black fly on a leaf
Image Credit: christels, Pixabay

Where Do Black Flies Come From?

Black flies come from rivers and moving water, which is where they lay their eggs and emerge as flies. Any region that has a lot of running water and wetter climates often experience big populations of black flies, causing outdoor activities to be much less enjoyable. Some states like Michigan and Minnesota have a massive spike in black fly population growth during the summer.

Are Horseflies the same as Black Flies?

No, horseflies are not the same as black flies, and they’re not from the same family. Horseflies come from the Tabanidae family, which is different from the Simuliinae family of flies. Horsefly bites might be more painful and will look different than black flies. Horseflies tend to be bigger and have soft black and white stripes on their heads. Horseflies are more aggressive than black flies, and their bites are also not dangerous to dogs, but they can transmit blood-borne diseases.

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How to Repel Black Flies from You and Your Dog

Although black fly bites aren’t usually a big deal, you can try to reduce the number of bites you and your dog suffer. They’re inevitable in some locations, however, so these solutions may not work. Here are some ways to help reduce black fly bites when you’re enjoying the outdoors:

  • Stay indoors if there are big swarms of black flies
  • Use vet-approved dog fly spray
  • Stay clear of rivers and moving bodies of water after rain or storms
  • Throw out garbage and keep garbage cans tightly closed
The dog is ferreting the garbage _frank60_shutterstock
Image Credit: frank60_shutterstock

Is it Safe to Use Human Bug Spray on my dog?

No! Do not use human-grade bug spray or mosquito repellent on dogs. DEET is toxic to animals and can cause a number of complications, so you should never use it on your pets. Buy a dog-safe, vet-approved spray for your dog to repel bugs and flies, checking that the product does not contain any toxic ingredients.

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Black flies are a common pest during the warmer months, often causing bright red marks on your dog’s skin. While they may look like hives or even poison ivy if there are multiple spots, their bites are not dangerous to dogs. As long as the bites don’t get infected or trigger an allergic reaction, black fly bites are not a danger to your dog.

Featured Image Credit: prochalen, Pixabay

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