Do Mosquitoes Bite Dogs? 5 Efficient Ways to Protect Your Pet

Do Mosquitoes Bite Dogs? 5 Efficient Ways to Protect Your Pet

Mosquitoes are pesky insects that can carry diseases like West Nile and Heartworm. Below are 5 efficient ways to protect your dog, and preventative measures against heartworm disease.

What Are Mosquitoes?

According to Companion Animal Parasite Council, mosquitoes are “a large and diverse group of flying insects.” Their life cycles consist of four distinct phases: egg, larva, pupa, and adult. In the United States, there are about 200 species of mosquitoes identified, and each species can display different behaviors, live in specific habitats, and even have different feeding behaviors. Only female mosquitoes feed on human and animal blood because it is necessary for egg production. Meanwhile, male mosquitoes feed on nectars and do not require blood meals. According to Pet Basics, mosquitoes can easily sense their meal from 65 feet away. These tiny pesky insects are one eager bunch! 

Depending on where you live, mosquitoes can live year-long but are more common in the warmer months. Mosquitoes are temperature sensitive and thrive in weather conditions with 75-80°F temperatures. With that being said, the dominant mosquito season usually starts in May and can last until late September or early October. The month of August is when the mosquito population is at its peak. 

mosquito bite in dogs

Do Mosquitoes Bite Dogs?

Yes, mosquitoes bite dogs. Mosquitoes are not picky eaters! These arthropods will drink blood off of any creatures, as long as they can get close to them. A dog’s thick fur may seem like a preventative barrier to mosquitoes but since these insects are tiny and quick, they can still latch onto the dog’s skin. 

What are the Symptoms of Mosquito Bites in Dogs?

It may not be noticeable at first since dogs are not bothered by it. Mosquitoes typically go for the ears, nose, mouth, and belly, though. The common symptoms of mosquito bites in dogs are visible bites or bumps on the skin; constant scratching and licking on the bitten area; skin irritation; and possibly even allergic reactions. Dogs will react differently to the bites. Some dogs can show no reaction at all even though they were just feasted on by blood-sucking insects, other dogs, however, may show extreme discomfort. They will get itchy, irritated, and hyper-focused on the affected area. 

If your dog is showing extreme discomfort from a mosquito bite, call your veterinarian for help. 

More Than Just a Bite

Mosquito bites are annoying but they can also pose much more serious issues. Since mosquitoes move freely and can feed on several hosts, they are known to be vectors of diseases. When a mosquito bites an infected host, the insect then gets infected too, and it can therefore spread diseases with every bite.

Types of Diseases Mosquitoes Carry

Other than a potentially severe allergic reaction that mosquito bites pose, several mosquito-borne diseases are identified both by CDC and CAPC. Diseases like West Nile virus and heartworm are common in dogs.

West Nile Virus (WNV) is considered the leading cause of mosquito-borne disease in the United States, according to CDC. It is more common for humans to get sick from the virus than dogs. A worse case of West Nile in humans and other animals like horses and birds causes encephalitis— a fatal infection that affects the brain. Fortunately for dogs—although they can still get infected—they do not develop encephalitis. The worst that can happen is they will experience seizures, muscle spasms, fever, decreased appetite, and depression. Dogs are also unlikely to spread the virus to humans and other animals. If you suspect that your dog is infected with West Nile, visit the veterinarian immediately. 

Other diseases mosquitoes carry:

  • Zika
  • Yellow Fever
  • Dengue 
  • Malaria
  • Chikungunya
  • Cache Valley
  • Eastern Equine Encephalitis

Heartworm Disease in Dogs

Heartworm is a parasite transmitted only by infected mosquitoes. When a mosquito bites an infected animal, it picks up microscopic worms called microfilaria (about 1/100th inch long). Then, when the now-infected mosquito bites another animal, it will drop infected larvae which will then enter the new host’s bloodstream. Once it enters the bloodstream, it will take 6 months for the larvae to mature into adult heartworms. And once it reaches the mature stage, it can live inside the animal for years. In dogs, heartworms can live for 5 to 7 years. The parasite can grow about a foot-long in length and can reproduce in the bloodstream. 

heartworm disease in dogs

(Photo Credit: LifeLearn Inc.)


Heartworms in dogs are dangerous and fatal. The parasite will circulate in the bloodstream and will attack the dog’s heart and lungs. During the early stages, an infected dog will not show any symptoms, but as the worms grow in length and number, the dog’s health will slowly deteriorate.

American Kennel Club identified four classes of infection:

  • Class one has no symptoms or just a mild cough.
  • Class two is marked by mild exercise intolerance and persistent cough.
  • Class three will result in greater exercise intolerance, abnormal lung sounds, weak pulse, syncope (fainting caused by impaired blood flow to the brain), decreased appetite, weight loss, and ascites (swollen belly due to heart failure).
  • Class four is known as caval syndrome, a life-threatening cardiovascular collapse, which is marked by labored breathing, pale gums, and dark coffee-colored urine, leading to complete organ failure and death.

Heartworms can be detected by administering blood tests, radiographs, ultrasounds, and echocardiography by a trained veterinarian. If your dog tests positive for heartworm, here’s what you should do:

  • Restrict exercise. Physical exertion can increase the damage to the heart and lungs caused by heartworms. 
  • Stabilize the disease. Before any treatment can begin, your dog’s condition must be stabilized first. Corticosteroid therapy, fluid therapy, diuretics, vasodilators, and positive inotropic agents are among the few clinical therapies that can be done to stabilize your dog.
  • Provide treatment. Only once your dog is stable can the veterinarian administer treatment. The vet will recommend treatment protocols depending on the severity of the situation. Dogs who have not progressed past class three can be injected with melarsomine dihydrochloride—an FDA-approved drug that goes under the brand names Immiticide and Diroban. Melarsomine can kill more than 90% of the worms present. Other treatments include heartworm preventatives, antibiotics, and steroids.
  • Surgery. If the case is extreme, the vet can decide to do surgery instead. The vet will physically pull out the heartworm from the dog.
  • Follow-up testing. Perform a follow-up heartworm test 6 months after the treatment. 
  • Prevent. To ensure that your dog will not catch the disease again, consider doing heartworm preventative measures. (More on this below). 

Protect Your Dog From Mosquitoes 

mosquito bites on dogs

Repel Mosquitoes on Your Dogs

You can repel mosquitoes on your dogs by avoiding stagnant water. Mosquitoes lay eggs on still waters, so if you see collected stagnant water in your space, get rid of it. You can also steer clear of wet, watery spots on your next hike.

When your dog is sitting outside in the summer months, provide them with a fan. Not only will this help to cool them down, but it will also repel mosquitoes. 

Best Mosquito Repellents

Mosquito repellents for dogs come in spray form, topical creams or gels, and chewable pills. 

Please be aware that regular bug sprays intended for humans are not to be used on dogs. DEET and Picardin are the two most common ingredients used in insect repellent for humans. Both chemicals cause vomiting, staggering, irritations, and seizures. Other ingredients to be wary of are citronella, geranium, marigold, garlic, and essential oils. Do not let your dog ingest any of these ingredients.

Below are suggested dog-friendly mosquito repellents. 

K9 Advantix II is a monthly topical treatment that kills fleas, ticks, and mosquitoes through contact. It also prevents mosquito bites on dogs. 

Vectra 3D is a fast-acting repellent that kills insects through contact. It kills and repels mosquitoes, reduces mosquito landings and bitings by 80%, and helps prevent heartworm.

Flea Away Natural Mosquito Repellent is a vitamin supplement intended to keep fleas, ticks, and mosquitoes away from dogs. When the vitamin is in your dog’s system, it produces a natural scent that is a deterrent to mosquitoes and other insects. Don’t worry though since the scent is undetectable to humans. Flea Away is a liver-flavored chewable tablet ideal for dogs who don’t like spray and topical repellents.

Avoid Being Outside When Mosquitoes Are Active

Mosquitoes are most active from the beginning of summer to late fall. They thrive in warmer conditions. It’s best to limit your dog’s exposure to the great outdoors during this period. Also, try not to go to swampy woodland areas or places with bodies of water (pond, lake, creek) that are common habitats for mosquitoes.  

Repel Mosquitoes at Home (and Around Your Place)

Prevent your home from getting mosquitoes by using door screens, bug sprays, and natural mosquito deterrents. Always clear out and clean vessels that may contain stagnant water like dog bowls, flower pots, and birdbaths. 

Prevent Heartworm with Medication

Heartworm treatments are hard and expensive, so prevention is the best way to go about it. Although there are no vaccines available for heartworm disease, monthly medications in the form of pills and topical ointment exist. Vets can also administer biannual injections. Consult your veterinarian for more information.

How to Treat Mosquito Bites on Dogs

There’s really not much you can do with a mosquito bite except monitor your dog for possible allergic reactions. The bite itself is not the issue here, rather it’s the potential disease your dog can get from the mosquito. If your dog is on heartworm medication, then there’s nothing to worry about. To be extra sure though, conduct heartworm testing on your dog at least once or twice a year. 


Mosquito bites are a nuisance to humans and pets alike. Other than the itchy bites, mosquitoes are dangerous as they can sometimes carry diseases like West Nile, Zika, and Heartworm. Heartworm disease is dangerous and can be fatal to dogs. Prevention is the best cure when it comes to heartworm so it’s advisable to put your pet on heartworm medication. 

Repel mosquitoes on dogs by using dog-friendly mosquito repellent, avoiding the outdoors during peak mosquito season, and clearing out stagnant water in and around your home.

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