Parasites in Dogs: Worms, Fleas, Ticks, and Mites

Learn Act
  • A dog could be infected with as many as 250 heartworms that are up to 16 inches long

  • You can have ticks in
    your own backyard…
    anytime of the year!

  • A dog with only 25
    fleas gets bitten 600
    a day

The Truth About Parasites in Dogs

Parasites, such as worms, ticks, fleas, and mites, are organisms that thrive by feeding off of other creatures. It’s common for dogs to become infected at some point in their lives, but left untreated parasites can cause serious damage to your pet's health and quality of life. Monitoring your dog for changes in behavior, eating habits or water consumption will help you determine if your dog has parasites.

Discover Which Dog Parasite Risks Exist in Your State
Click a state on the map below to get important information about your region’s parasite risk. See National Parasite Risk »

Some infected dogs have no symptoms. The only way to detect and properly treat internal parasites is through testing.

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There are many parasites that can be harmful to your dog’s health. Let’s take a closer look at some of them.

Worms in Dogs

Though they are one of the most dangerous parasites in dogs, heartworms are extremely preventable. They are transmitted by mosquitoes and live in the heart and blood vessels of the lungs. Heartworm infection can affect many different organs of the dog but signs of heart and lung disease are most common.

Roundworms can be contracted in many different ways, frequently from a mother to her unborn puppy. Because there are so many ways for your dog to be infected with roundworms, they are very easy to spread. It is essential to keep your dog’s living area clean and prevent them from eating wild animals.

The name “hookworm” is derived from the hook-like mouth-parts these parasites use to anchor themselves on the lining of the intestinal wall. Puppies should be treated for hookworm at 2,4,6 and 8 weeks of age due to the high rate of hookworm infection in newborn puppies.

Tapeworms are long, flat worms that attach to your dog’s intestines. Dogs commonly contract tapeworms from fleas, mice and other rodents and segments of the worms are often found in on your dog’s rear or in their feces. Though there are few symptoms associated with tapeworms, it is still important to treat them as soon as possible.

The whipworm is a common intestinal parasite in dogs. The parasites reside in the cecum, where the small intestine and large intestine meet. Whipworms can be difficult to diagnose because there are few signs of infection, so regular checkups are important.

Skin Parasites: Scabies, Ticks, Mites, and Fleas in Dogs

Caused by a highly contagious skin parasite, scabies tend to burrow in your dog’s skin which can result in scabs and hair loss. Scabies causes severe itching which can lead to intense and prolonged scratching.

They are found in grassy or wooded areas and can attach themselves to you and your pet as you pass by. Although a tick’s bite does not itself pose a direct threat to your dog’s health, it can transmit serious (and sometimes fatal) diseases such as Lyme disease and Rocky Mountain fever.

Ear Mites
Barely visible to the human eye, ear mites live on the surface of ear canal skin. As these microscopic parasites feed in a dog’s ear canal, they cause intense itching. A dog suffering from ear mites may be seen repeatedly scratching at his ears or violently shaking his head. If you see dark flecks resembling coffee grounds in your dog’s ears, these are the mites' droppings.

Fleas can make any dog’s life miserable (and their family’s)! These small, blood-sucking insects like to feed on your dog and live anywhere your dog does. Fleas can quickly cause a long-lasting, major infestation in your home. Not only can fleabites cause discomfort, itchiness and severe skin reactions, they can potentially transmit tapeworms if accidentally ingested by your dog.

Other Internal Parasitic Dog Diseases

These tiny single-celled parasites, usually found in puppies, live in your dog’s intestinal lining. Dogs become infected with by swallowing soil that contains coccidia. Left untreated, the parasites can cause diarrhea, weakness and dehydration.

Three Ways to Protect Your Dog Against Parasites

Get your Dog Tested Regularly
While it’s fairly common for a dog to become infected with an internal or external parasite at some point, early treatment is crucial. A harmless parasite left untreated could eventually cause a life-threatening illness for your dog and pose a health risk to your family.

Focus on Prevention First
Preventative medicine is a much better option than costly treatments later. Getting your puppy or dog vaccinated and de-wormed regularly allows her immune system to thrive. Adult dogs also benefit from fecal examinations - which allow your veterinarian to diagnose parasites not controlled by monthly medications.

Bring your Dog in for an Annual Checkup
Bringing your dog to your veterinarian for regular parasite checkups is one of the most important things you can do to keep your dog, and your family, healthy. We offer different programs specifically designed for your dog’s stage of life. Schedule an appointment to find out more.

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Learn More About How to Prevent and Treat Parasites »

From Our Pet Health Library

  • Heartworm is 99.9%
    with safe and effective medicines

  • A dog can get multiple
    from a single
    tick bite

  • Fleas can transmit
    tapeworms to you &
    your dog

Tips on Preventing and Treating Parasites in Dogs

    Dog Parasite Prevention Tips
  • Have your dog examined at least annually by a veterinarian
  • Feed your dog cooked or prepared food and fresh water
  • Keep your yard clean and supervise your dog so they do not come in contact with feces and fluids
  • Feed your dog a balanced diet and consider vitamin supplements to keep his immune system strong
  • De-worm puppies at 2, 4, 6, and 8 weeks of age

The Key to Treating Your Dog’s Parasites
If your canine companion does happen to contract a parasite, the best course of action is to treat quickly and completely. Treatment will vary depending on whether the parasite is one that lives outside the body such as fleas, ticks and mites or inside the body, like whipworms, heartworms or ringworms. Though some parasites, like fleas and ticks, can be treated with shampoos and powders, most anti-parasite products require a prescription from your veterinarian.

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VCA Home Delivery - Easy to Remember!
Did you know that one of the biggest hurdles in preventing parasite infestation is making sure that protection is administered regularly? To make sure you don’t forget your dog’s parasite medication, VCA offers you convenient home delivery service!

    VCA Home Delivery advantage:
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From Our Pet Health Library