No pet is safe from pesky parasites, whose effects can range from minor nuisance to extreme discomfort or serious health complications. The Tender Touch Animal Hospital team considers parasite control an essential component of preventive veterinary care, and we want to help pet owners understand how parasites can impact their furry pal’s health. Here, we explain parasite types, testing recommendations, and treatment options.

External parasites and pets

External parasites live outside your pet’s body, often feeding on their blood and frequently causing itching, skin irritation, and hair loss that may become extreme in pets who develop parasite allergies. External parasites can also transmit serious diseases, making them a major health threat. Common external parasites include:

  • Fleas — Fleas are small, winged insects that complete most of their life cycle living and feeding on their host. When fleas reproduce, the eggs stay in the environment and hatch a few weeks later, making eliminating them from your home and pet a lengthy process. Fleas frequently cause allergic reactions and may transmit tapeworms, cat scratch fever, or the plague. 
  • Ticks — Ticks are free-living, but they must attach to and feed on a host’s blood each time they molt or lay eggs. Ticks are notorious for carrying diseases, including Lyme disease, anaplasmosis, and ehrlichiosis, which can lead to chronic illness or death in dogs.
  • Mites — Mites are visible only under a microscope. These tiny creatures burrow in a pet’s skin, oil glands, ears, or hair follicles, creating intense inflammation and sometimes extreme itching. Mite infestations are also called mange, and some mite species (e.g., sarcoptes) are contagious to humans.

Internal parasites and pets

Internal parasites live inside your pet’s gastrointestinal (GI) tract or other organs. Effects depend on the organ targeted by the parasite and range from mild diarrhea to catastrophic organ failure. Common internal parasites in pets include:

  • Roundworms, hookworms, and whipworms — These intestinal worms are commonly identified in young puppies and kittens, because they can reactivate in a previously infected pregnant mother. Older pets can contract worms by consuming infective eggs, which are deposited on feces. Children are at risk for contracting roundworms from infected pets.
  • Tapeworms — Tapeworms are also intestinal parasites, but they are long, flat, and segmented in contrast to the other worms’ round bodies. Tapeworm segments contain eggs that look similar to dried rice grains, which make their way outside a pet’s body and settle on feces, hair, or bedding.
  • Protozoa — Giardia and coccidia are single-celled microscopic organisms. They are  tiny, but they can pack a mighty punch by causing watery diarrhea in infected pets. Giardia is likely the most common intestinal parasite in dogs, can live in asymptomatic pets, and spreads quickly.
  • Heartworms — Heartworms are large worms that live in the heart, lungs, and surrounding blood vessels. They are transmitted by mosquitoes that pick up and harbor the immature heartworms from other infected pets. In dogs, heartworms damage the heart over time, leading to eventual heart failure. In cats, heartworms can cause severe respiratory disease or sudden death.

Pet parasite testing

Routine parasite testing is essential for detecting and identifying unwanted hitchhikers. External parasites can be identified on physical examination or by using a skin scraping technique to check for microscopic mites. Additional tests recommended for most pets include:

  • Fecal floatation — At least once annually, or more frequently for social or otherwise high-risk pets, this test studies a stool sample for worm eggs and protozoal cells.
  • Heartworm test — This blood test, which is recommended annually for dogs, looks for evidence of adult heartworms. 

Pet parasite treatment and prevention

Preventing parasites is typically easier and more cost-effective than waiting until a pet is infested. Parasite prevention products are available as oral or topical medications, are typically administered monthly, and provide residual protection throughout the treatment period. Flea and tick prevention products can treat existing infestations and prevent new ones. Heartworm preventives kill immature worms but cannot treat infections that have progressed to the adult stage. 

Routine deworming with oral medication is recommended to clear intestinal worms from puppies and kittens. As adults, pets who take heartworm preventives year-round are protected against common intestinal parasites and don’t typically require additional treatments. Dogs with heartworms can be treated with a lengthy and painful series of injections and cage rest, but no treatments are available for cats.

Regular parasite testing and adhering to preventive medication schedules are critical to maintaining your furry pal’s health. For questions about common parasites, to refill your pet’s parasite control medications, or for assistance developing a parasite treatment plan, contact our Tender Touch Animal Hospital team and schedule a visit.