Parasites may seem like a small problem, but these tiny—sometimes microscopic—pests can cause big health problems for pets and people. Fortunately, prevention is easy, safe, and effective.

To help you better understand how you can protect your pet, home, and family from harmful parasites, the Guardian Veterinary Care team has compiled a handy guide that includes our most frequently asked parasite questions, along with our answers.

Question: What are parasite risks for pets?

Answer: External parasites, such as fleas, ticks, mosquitoes, and mites, prey on your pet’s skin and feed on their skin cells or blood. External parasite risks include:

  • Harmful or deadly diseases — Ticks can transmit multiple infectious diseases, including Lyme disease, anaplasmosis, and ehrlichiosis. Fleas can cause anemia in smaller pets and tapeworm infection in all pets. An infected mosquito’s single bite can transmit life-threatening heartworm disease.
  • Flea infestation — One female flea can lay as many as 50 eggs per day in the surrounding home environment, such as carpet and pet beds.
  • Intense irritation or allergy — Pets can suffer local or generalized irritation at the bite site and will scratch, bite, and lick the affected area, or all over their bodies. Pets with flea allergies may react to a protein in flea saliva and experience severe discomfort and hypersensitivity.

Intestinal  parasites, such as worms or single-celled protozoans like Giardia, primarily dwell in the pet’s intestines and can cause a variety of problems, including:

  • Nutrition deficiencies — GI parasites can damage the intestinal wall and interfere with your pet’s ability to absorb nutrition from food. 
  • Anemia — Some GI worms (e.g., hookworms) bite and feed on the intestinal lining. Heavy worm burdens can cause anemia in smaller pets, especially puppies and kittens.
  • GI upset — GI parasites can disrupt gut function and may cause vomiting, diarrhea, and/or loose stool. 

Q: How do pets get parasites?

A: Parasites are virtually everywhere, especially in warm, humid environments or where pets are kept in high volume or unsanitary conditions. They can be transmitted through several routes, depending on the individual parasite. The most typical infection locations include:

  • Pet facilities (e.g., grooming, training, or boarding)
  • Shelters and animal control centers
  • Dog parks or day care facilities
  • Pet supply stores
  • Wildlife areas

Infection routes vary by parasite, but can include:

  • Fecal-oral (e.g., contact with contaminated feces or soiled materials)
  • Direct contact (e.g., external parasites landing or crawling on the pet)
  • Transcutaneous (i.e., through the skin) or transplacentally (i.e., during pregnancy)

Parasite-to-pet transmission of infectious diseases (e.g., heartworm, tick-borne diseases) involves the parasite biting and feeding on the pet. The parasite injects infectious material beneath the pet’s skin through the saliva as they bite.  

Q: How can I protect my pet from parasites?

A: Because parasites are so pervasive, protecting your pet requires a multi-step defense. At Guardian Veterinary Care, our veterinarians recommend a comprehensive parasite prevention plan that includes:

  • Prescription parasite preventives — All pets should receive a year-round flea, tick, and heartworm medication that will also protect them from most intestinal worms and external mites. The products are available in oral, topical, and injectable formulations.
  • Annual parasite screening tests — Annual or bi-annnual intestinal parasite screenings (i.e., fecal testing) identify occult or hidden infections via microscope. Heartworm and tick-borne disease screenings are a simple blood test that can detect heartworm disease or your pet’s exposure to disease-carrying ticks. 
  • Environmental management — Discourage parasite populations and reduce your pet’s exposure risk by keeping their environment clean and tidy. This includes:
    • Trimming grass and clearing debris
    • Removing pet waste from the yard 
    • Relocating wildlife feeding stations
    • Keeping your pet clean and groomed
    • Avoiding communal pet areas (e.g., dog parks)
    • Vacuuming carpets and washing pet bedding weekly

Q: How does parasite prevention protect human health?

A: Several parasites, including intestinal parasites, are zoonotic, meaning they can be transmitted from pets to humans and cause infection. Infection risks are greater for vulnerable populations, such as children, immunocompromised people, and the elderly. A comprehensive parasite prevention plan protects people as well as pets, because your pet can’t be infected with—and therefore can’t transmit—parasitic organisms or eggs.

Q: How often does my pet need a parasite preventive?

A: Guardian Veterinary Care recommends year-round heartworm, flea, and tick prevention for all pets, including those who live exclusively indoors. Although some parasites are less active during the winter, most remain active throughout the Pacific Northwest’s mild winters and can infect unprotected pets. Additionally, external parasites can sneak indoors through open doors or broken window screens, or ride inside on shoes, bags, or other pets.

Talk to your veterinarian if your pet isn’t currently receiving parasite preventives. Your veterinarian may suggest testing to ensure your pet is healthy and disease-free before they resume preventives.  

Q: Is parasite prevention safe for pets?

A: Social media groups have created an unfortunate negative bias and fear against pet parasite preventives, and many pet owners have abandoned the products and put their pets at risk for dangerous disease. And, although no pharmaceutical product can be guaranteed 100% side-effect free, the brands and products that we recommend have undergone rigorous clinical testing and been proven safe when administered according to label directions. Our veterinary team has trusted the products we recommend for many years.

Because each pet is unique, our veterinarians will take your pet’s breed, age, health, and lifestyle into account before making a customized parasite preventive recommendation. This extra step provides an extra level of safety and efficacy, and peace of mind, because you know your pet’s preventives are matched to their needs and lifestyle.

Don’t let your pet become a victim of pesky parasites. Contact Guardian Veterinary Care to schedule your pet’s annual parasite screening testing and receive personalized preventive recommendations.