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A Guide to Pets and Parasites

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Parasites can be tricky and affect any cat or dog, regardless of age, breed, or health. With so many different parasites, including internal and external, these can range from a simple nuisance to a significant health condition.

Parasites in Pets

Parasites are tiny organisms that can live in or on their host at the host’s expense. Both cats and dogs can be affected by parasites to varying degrees. Sometimes the parasites can go unnoticed for some time, with only a few minor symptoms affecting their host (your pet). In other instances, parasites can quickly begin to affect your pet in a negative way and cause a slew of symptoms that could worsen their health. Not to mention, depending on the type of parasite your pet contracts, it could even begin affecting you and the others in your household.

Intestinal Parasites in Pets

An intestinal parasite is just as its name suggests—it’s a parasite that lives internally, typically in the gastrointestinal tract, though it can technically live anywhere inside its host.

With canines, some of the more common internal parasites include hookworms, roundworms, heartworms, tapeworms, and ringworms. Whenever these parasites reach a dog’s intestines, they can cause issues, some of which could be life-threatening. If you have a puppy, intestinal parasites can cause them to have poor growth and not develop properly. A dog with a weakened immune system or other health issues who gets an intestinal parasite could mean a much more serious situation. Heartworm, for instance, can be a life-threatening condition if your dog does not receive proper treatment in a timely manner.

Cats can be affected by the same type of worms as dogs, including hookworms, roundworms, heartworms, tapeworms, and ringworms. In young kittens, any of these intestinal worms can cause serious issues. Even with adult cats, tapeworms can still possibly cause intestinal obstruction, roundworms can affect a cat’s growth and development, and hookworms can cause anemia, which is when there’s a decrease in their red blood cell count.

External Parasites in Pets

Cats and dogs can also be affected by external parasites, such as fleas, ticks, or mites.

  • Fleas

    Fleas often make an appearance when the weather becomes warmer and more humid. So, depending on where you live, fleas may be around for just the summer season, or they may be present for most of the year. If your pet comes in contact with an area where a flea infestation exists, it’s possible for them to get fleas.

    Unfortunately, if your pet picks up fleas, you may not notice for some time—fleas are tiny. The longer fleas stay on your pet, and the more there are, you may begin noticing more symptoms. Minor reactions include some redness on their skin, but more severe ones include frequent scratching that can lead to sores or infections. If your pet bites at their itch instead of using their paw, it’s also possible for them to ingest fleas which could lead to further health issues.

    In the instance that your cat or dog’s flea issue becomes more severe, these fleas could get into their environment, including their bed, your carpet, and your furniture. If this happens, you may need to treat your home with insecticides and do some thorough cleaning, particularly in the areas where your pet sleeps.

    To help avoid fleas altogether, treat your pet with a preventive during flea season or as recommended by your veterinarian.

  • Ticks

    There are many different types of ticks, which may also be more prevalent during certain times of the year, based on your geographic location. Ticks are usually found in wooded areas, brush, or tall grass. Any pet, or person, for that matter, that enters these types of places is at risk of picking up ticks, which can carry other infectious diseases.

    Since cats spend most of their time indoors, they are at less risk than dogs of picking up ticks. Anytime you go hiking with your dog or notice them walking through tall grasses, thoroughly check them afterward for any ticks. If your pet has darker-colored or thicker fur, take extra care to ensure you don’t miss any.

    If you find a tick on your pet, you can follow the same methods as though you were removing one from yourself. Use tweezers, not a match, and grab the tick as close to your pet’s skin as possible. Remove it gently without twisting or pulling too quickly. This can reduce the risk of leaving part of the tick in your pet’s skin.

    Similar to fleas, it is recommended that you give your pet a tick preventive to help reduce the likelihood of them getting ticks in the first place.

  • Mites

    There are a few different types of mites, and they can live in pet’s ears (ear mites) or on their skin. Like other types of external parasites, mites will usually cause excessive itching. This can help indicate that something is wrong. In the instance that your pet has ear mites, you may also notice them scratching their ears more than usual or excessively shaking their head. Mites are also the cause of mange, a well-known skin disease in dogs that’s more often found on homeless or rescue pets who have been living in unideal situations.

    If your pal is diagnosed with mites, treatment will vary slightly based on the type of mites they have and how far their condition has progressed. In many cases, your veterinarian may recommend cleaning the infected area, such as their ears, or applying ointment to help soothe their irritated skin. Along with prescribing a medication that can help kill the mites, it’s recommended that you thoroughly clean your home, especially your pet’s bed and any area they like to spend their time.

Though it may initially sound like a lot, one of the best ways to keep your pal safe and healthy is to keep their environment clean, keep up with their grooming requirements, and give them preventive medicines when necessary.

Blood Parasites in Pets

From their name alone, you can most likely infer that blood parasites are parasites that live in their host’s blood. There are a handful of different blood parasites in both felines and canines, and they can differ from single-celled protozoa to more complicated bacteria. Just as the parasite can vary, so can the degree of symptoms they cause. Some may only cause slight reactions and mild sickness, while others can lead to serious health issues or even shorten your pet’s lifespan. Blood parasites can be transmitted through ticks and fleas.

Giardia in Pets

Giardia is another type of parasite that can affect people as well as pets. Cats and dogs can become infected when they ingest the parasite. After reaching the intestines, it can progress, and your pet can begin showing signs such as diarrhea. Some pets may also experience vomiting and, over time, weight loss. In some cases, it’s possible for pets to be carriers of this parasite without ever showing signs. The good news is that with proper treatment, which usually involves administering medication, your pet will most likely make a full recovery. Normally, pets that are much younger, older, or have a weakened immune system will take longer to recover. Either way, having your pet retested a few weeks post-treatment is essential.

orange and white cat with a red collar by a window

How Do Pets Get Parasites?

Depending on the parasite, pets can pick them up in several ways. Many external parasites can get onto your pet just from their environment. Other times, it can depend on what your pet eats or if they drink contaminated water. Parasites can also be contagious, so if one of your pets has them, they can be transmitted to your other cat or dog.

If your dog spends a lot of time outside, there’s a chance they could get bit by a spider or ant or even stung by a bee. Learn what to do if your best pal has a run-in with an insect.

How To Treat Parasites in Pets

Initially, it may seem overwhelming how many different parasites can affect your cat or dog. Thankfully, most common parasites that pet parents deal with have treatment options.

To help your pet have the most successful treatment, it’s essential that once you begin noticing symptoms or suspect that your best pal may have a parasite, you will need to take them to their veterinarian as soon as possible. Your veterinarian will most likely perform a thorough exam and run a few tests in order to get a complete picture of your pet’s condition. Once diagnosed, you and your veterinarian can discuss the treatment plan, including what medications your cat or dog may need and any additional care-taking steps you should take.

It's crucial that you follow your veterinarian’s advice in order to help your pet feel better and get back to their normal, healthy self. Don’t hesitate to reach back out to your veterinarian if you believe the treatment isn’t working as well as it should.

Knowing what to do if your dog comes across these microscopic parasites is incredibly helpful as a pet parent, but learning what to do if your canine friend also has a run-in with a larger critter, such as a skunk, can also be rather beneficial.

Preventing Parasites

Although it is undeniably important to understand the causes and treatment options for parasites, knowing how to prevent them in the first place could arguably be even more significant.

For parasites such as fleas, ticks, and heartworm, it’s typically recommended that you give your pet a monthly preventive. These can be found in chewable pills, liquid medicine applied to your pet’s skin, or collars your pet wears. There are various brands and prices as well, so it can be beneficial to do your research ahead of time and talk with your veterinarian about their recommendations.

How To Prevent Parasites in Dogs

Since our canine pals spend much of their life outdoors, getting into and eating things they arguably shouldn’t, this means that preventing parasites in dogs should be a priority for their entire life.

Along with the preventive medicines for external parasites, keep an eye out for anything abnormal (including skin redness) whenever you brush your dog. Be aware of flea and tick season for your area, and after hikes, always do a thorough check for ticks.

Keep your dog away from other animals that may have a parasite, and don’t let them drink out of possibly contaminated water. Another preventive measure is to clean your home regularly, including your pet’s toys, bed, and any blankets they may use.

How To Prevent Parasites in Cats

A great way to protect your feline friend from parasites is to keep them indoors. Not allowing your cat to roam outside can protect them from parasites, diseases, other animals, and dangers like cars.

Following the same guidelines you would for a dog, you should give your cat a monthly preventive, keep them away from any other pet that may have a parasite, keep an eye on their skin and fur, and regularly clean your cat’s bed and any place they may often hang out.

Does Pet Insurance Cover Parasites?

Every pet insurance provider has its coverage options and plans, so, depending on the ones you choose, they may help cover the costs related to parasite treatment.

The information presented in this article is for educational and informational purposes only and does not constitute or substitute for the advice of your veterinarian.


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