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Whipworms In DogsUpdated 10 months ago

Whipworms are an intestinal parasite of dogs. While mild infections may go unnoticed, if the worm count increases then bloody diarrhea or blood loss anemia can result. Eggs can infect or re-infect even after being in the soil for a long time.

My Dog Tested Positive For Whipworms

Finding whipworms or whipworm eggs in your dog’s stool sample likely means your dog is infected with whipworms and should be treated with a deworming medication. A test result is not the same as a veterinarian’s diagnosis, so it’s always best to consult with a veterinarian about your dog’s test results to determine the safest and most effective treatment and prevention plan, and when to do follow-up stool tests.

MySimplePetLab Routine Dog Stool Tests report positive whipworm results using a quantitative estimation scale of 1 (1 egg or parasite was seen), 1+ (2 to 4 eggs or parasites were seen), 2+ (5 to 10 eggs or parasites were seen), 3+ (11 to 50 eggs or parasites were seen), or 4+ (>50 eggs or parasites were seen) per (approximately) one gram of stool. This is based on both a naked-eye visual and then a microscopic exam of the stool after special preparation and centrifugation techniques. This scale provides some perspective on the potential burden of worm infection (more eggs likely means more worms in the intestines).

Most veterinarians will recommend rechecking a dog’s stool sample 2-4 weeks after treatment for whipworms. If you have other dogs in the household, they should be tested as well since whipworms in one dog can often mean whipworms in more than one dog.


My Dog Tested Negative For Whipworms

If your dog had a stool O&P (fecal ova and parasite) test and whipworms were not seen, that is great news. It may mean that you are doing a good job preventing whipworm infections by regularly deworming your dog or maybe, you and your dog were just lucky! Either way no one wants their dog or puppy shedding whipworm eggs into the home or community environment, putting other dogs at risk of infection, your dog at risk of re-infection, or you or your human family at risk of infection. Most veterinarians recommend retesting your adult dog for whipworms every 6 to 12 months.

Keep in mind that it’s possible for dogs to have whipworms without their eggs being found in the stool test (called a “false negative” result); especially if the infection is mild (very small number of worms) or is recent (whipworms are still too young to shed eggs) or a male-only infection. False negative results for whipworms can also occur because eggs are not always present in every stool sample and because they are more challenging to tease out of the stool (compared to roundworm and hookworm eggs) in the laboratory even when present. Also depending on their lifestyle, dogs can remain at risk of whipworm egg exposure so a negative test result today doesn’t mean it couldn’t be positive later. This explains why regularly testing for whipworms (1-2 times per year in adult dogs; 3-4 times for puppies) is recommended throughout the dog’s life.

Learn More About Whipworms

What are Whipworms?

Named for their whip-like bodies, whipworms (Trichuris vulpis) are intestinal parasites that can infect and sometimes cause harm to dogs of all ages. Dogs get them by accidentally ingesting the infective eggs from contaminated grass/plants or soil. The swallowed eggs hatch and attach to the inner lining of the large intestines to feed on the dog’s blood and tissue fluids of the intestinal lining. Surprisingly, many dogs don’t show any symptoms from mild infections but more severe infections (larger number of whipworms) can result in severe inflammation that leads to diarrhea, bloody stools, or even blood loss anemia.[1,3,4]

How Common are Whipworms?

Canine whipworms are worldwide and found in dogs, foxes, and coyotes in the U.S. While found less commonly than some other worm types, a previously infected dog is often at high risk of re-infection. This is because whipworm eggs are notoriously resistant to drying and heat, so they can remain in the environment for many years. Dogs frequenting areas with infective whipworm eggs are at constant risk of infection or re-infection.[1,5]

What do Whipworms look like?

Adult whipworms are only about ¼ inch in length and named for their whip-shaped bodies. The front end of the worm with the mouth looks like the thin end (“lash”) of a whip (about 75% of their length) which they thread into the lining of the dog’s intestine. The back end of the worm with the reproductive organs looks like the thick (“handle”) of a whip (about 25% of their length).[4] Adults are thin and small but when passed in stool can be seen with the naked eye.[5]

The football or barrel-shaped eggs of whipworms are only detectable by examining a stool (fecal) sample under a microscope (MySimplePetLab Routine Dog Stool Test). If found, it’s a giveaway that adult whips have infected the dog and treatment is needed.

 What Symptoms Are Caused By Whipworms?

Many dogs infected with whipworms don’t show any symptoms, especially if the number of worms in the intestine is low.[5] Infections with high worm numbers can lead to irritation and bleeding from the lining of the intestines. This can result in symptoms such as diarrhea, bloody stools, mucus stools, dehydration, blood loss anemia, weight loss, and in severe cases, even death.[1,2,3,5]

If your dog is acting sick, please contact a veterinarian right away.

How Do Dogs Get Whipworms?

Dogs get whipworms in only one way, by mouth. They accidently swallowed infective eggs from grass, plants, soil or drinking contaminated water where stool with whipworm eggs had decomposed. Puppies get whipworms in the same way and not from the mother’s womb or milk.[5]

Eggs passed in the dog’s stool will be ready to re-infect the same dog or other dogs in about 1-3 weeks. These infective whipworm eggs are resistant to harsh outdoor conditions and can remain viable for many years. Dogs who have tested positive for whipworms should be dewormed for whips regularly thereafter. Promptly cleaning up stool from areas where dogs frequent can help prevent whipworm transmission.[5]


What Is The Whipworm Lifecycle?

The life cycle of the dog whipworm is simpler than other worm life cycles. Dogs accidently swallow the infective eggs when eating contaminated soil or vegetation like grass or plants. The eggs pass into the dog’s small intestine where the larvae hatch and burrow into the lining (mucosa) of the intestine to grow for a week or two. Then they move to the large intestine where they bury their thin, mouth ends (“lash” of whip) into the mucosa. Here they feed on the dog’s blood and tissue fluids. The larger, reproductive tail-end (“handle” of whip) hangs in the intestine and will start releasing eggs into the stool in about three months.[3,5] Each female whipworm can produce more than 2,000 eggs per day.[3]


Can People Or Other Pets Get Whipworms?

People are very unlikely to get infected with whipworms.[5,7] There are occasional reports of infections (Trichuris vulpis) from accidentally ingesting the eggs in contaminated dirt or on unwashed, contaminated fruits or vegetables. These rare infections typically have few or no symptoms, and are readily treated.[7]  Practice good hygiene by thoroughly washing your hands with soap and water (get those thumbs too!) after touching stool, soil, and other materials that could be contaminated with pet stool.

Whipworm infections appear to be rare in domestic cats in North America; occurring more commonly in tropical areas.[5] Transmission of whipworms between dogs and cats is unlikely.

Whipworms eggs are very sturdy and can last in the environment for years. Stool testing your dog, regular deworming for whips (especially for dogs that previously tested positive for whips) and picking up stool right away will prevent spreading whips to other dogs in the household and community.

 How Are Whipworms Prevented And Treated?

Since whipworm eggs are very difficult to clear from contaminated soil, it’s best to prevent them from getting there in the first place. This is done through regular stool (fecal) testing, deworming (especially for dogs that previously tested positive for whips), and cleaning up dog stool quickly so the eggs can’t remain in decomposing stool and become a source of infection for other dogs or re-infection of your dog.

Once a whipworm infection (Trichuris vulpis) has been positively identified in your dog’s stool, veterinarians usually recommend deworming.

It’s also common for veterinarians to recommend deworming whipworms monthly for dogs who previously tested positive to prevent infection from resurfacing. This is because whipworm eggs are notoriously hardy so can last years in the environment, making risk of reinfection high.[2,4,6]  Fortunately for dog owners, there are flea and heartworm preventatives that include medications like milbemycin oxime or moxidectin to provide protection against whipworms.[3,4, 5]

Where Are Whipworm Medications Purchased?

While MySimplePetLab does not dispense or prescribe medications, there are several deworming medications available over-the-counter (OTC) and through veterinarians for whipworm prevention and treatment. Typical whipworm medications are febantel, fenbendazole, moxidectin, and milbemycin oxime. Some flea and heartworm preventatives include milbemycin oxime or moxidectin as a monthly whipworm treatment for dogs. These types of preventatives are often recommended in environments where re-infection is likely.[5]

It’s always best to consult with a veterinarian prior to administering any whipworm medication, even an OTC version, to make sure it will be safe and effective for your pet. Always read the medication administration directions carefully and be on the lookout for potential side effects (like vomiting) when any deworming medication is administered.[5]


When/How Is Dog Stool Tested For Whipworms?

Veterinarians recommend stool (fecal) testing puppies 2 to 4 times during their first year of life, and 1 to 2 times each year in adult dogs (every 6 to 12 months).[2] Veterinarians often call this stool test a “Fecal O&P”, with the O&P meaning “ova (eggs) and parasites”. It includes special preparations of the stool sample and analysis using a microscope to look for certain types of parasites like whipworms. This same test is also used to recheck stool samples after treatment. Typically, a “recheck” stool test is done 2-4 weeks after deworming a dog or puppy that was treated for whipworms to help confirm that the treatment was effective.

Puppies and dogs should also be tested when symptoms of possible whipworm infection are present such as diarrhea, bloody stools, mucus stools, dehydration, blood loss anemia, or weight loss. Please contact a veterinarian right away if your dog is acting sick.

Some veterinarians still do the Fecal O&P at their practice with trained veterinary technicians. Most however, “refer” or ship their patient’s stool samples to an external animal reference laboratory for preparation (including centrifugation), analysis, and reporting, where the laboratory technicians and testing processes are more specialized.

With the simple and convenient MySimplePetLab testing solution from home (MySimplePetLab Routine Dog Stool Test), you can directly access this same professional reference lab testing for whipworms that veterinary professionals use every day. MySimplePetLab uses reference quality stool preparation techniques and centrifugation, along with a highly trained laboratory team to maximize the likelihood of finding whips and their eggs if present in the sample.


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