Information

What are Roundworms and Why Should I Care?


What are they?

Roundworms are the most common intestinal parasite in dogs and cats. The adult worms are round and range in size from less than two inches to almost 6 inches in length. According to the Companion Animal Parasite Council, a survey conducted in 1996 using samples collected from across the United States found that more than 30% of dogs younger than 6 months of age were shedding roundworm eggs and other studies have shown that virtually all pups are born infected. Other surveys have found more than 25% of cats infected.

How does my pet get roundworms?

Because the larval stages of the worms migrate inside the animal, some of the worms become encysted and lie dormant in the host animal’s organs. When the female becomes pregnant, those hidden parasites can become active, mature, and be passed to the puppies or kittens across the placenta before they are ever even born. Sometimes the worms pass into the mother’s milk so the young ones are exposed again when they are nursing. Cats and dogs can also become infected by licking and/or eating grass and dirt and other soiled items that contain infective eggs or by eating prey animals that have already been infected.

What disease does it cause in my dog or cat?

The migrating larvae travel through the body causing damage primarily to the liver and the lungs with most of the clinically significant damage occurring in the lungs and resulting in coughing and respiratory problems. Once adult worms form in the gastrointestinal tract, your puppy or kitten may develop vomiting, diarrhea , bloating and abdominal discomfort.

Can my pet give the worms to me?

Roundworms are not transmitted between people to other people. And they are not directly passed from dogs and cats to people. Affected dogs and cats shed eggs in their feces. The eggs mature into the infective stage of the parasite in the environment and are then swallowed with dirt that is either eaten on purpose (pica) or inadvertently (through inadequate care and hygiene). The infective larva do not progress to adult worms in people but the migrating larvae leave the intestines and find their way to other organs such as lungs, liver, or eyes and cause damage and disease in those locations.

Note that wild animals, especially raccoons, commonly carry roundworms and can also be a significant source of environmental contamination in places where they share outdoor areas with us and with our pets. Human infection with raccoon roundworms can be especially serious so do not feed or otherwise encourage raccoons around your home.

What diseases do roundworms cause in people?

People are not the definitive, natural host for roundworms which means that the roundworm lifecycle is not completed in humans. We do not develop adult worms. In infected people, it is only the immature, migrating larvae that produce the illness. Fever, abdominal pain, difficulty breathing can occur as larvae move throughout various organs and systems in the body. If the larvae travel to a person’s eyes, their presence can cause inflammation and redness and even blindness.

According to the Centers For Disease Control approximately 14% of people in the United States test positive to antibodies against roundworms. That does not mean that those people have significant, clinical disease but it does mean that at some point in time those individuals were exposed to roundworm larvae which resulted in their bodies producing antibodies in an effort to clear the infection.

How is a roundworm infection treated?

In people roundworm larvae infections are often self limiting since the worms cannot undergo their complete life cycle in humans. If illness does occur, as can be the case especially in young children, your physician will decide on the best course of treatment given the particular circumstances.

In pets, there are many products that are safe and effective in treating roundworm infections.

Since so many puppies and kittens are already infected at birth, it is very important that all of them are given appropriate worming medication at 2, 4, 6 and 8 weeks of age. Likewise all new pets (regardless of age) should receive treatments as soon as possible. The goal is not just to try to avoid infection but also to stop the shedding of eggs in the stool before they contaminate your environment and become an ongoing source for infection for your pets and your family.

Better yet, how do I prevent roundworm infections?

A single adult, female roundworm can lay hundreds of thousands of eggs in one day; and the eggs are very difficult to kill in the environment and can survive for years. Remember, however, that the eggs that are shed in the feces are not yet capable of causing infection. Depending on environmental conditions, it can take 1 to 4 weeks or so for that development to occur. Therefore, be diligent about cleaning up after your pets. Dispose of all feces promptly - at least once a week.

Wash your hands and your children’s hands frequently - after handling pets, pet waste, gardening/working in the soil, or playing in sand boxes/playgrounds. Wash vegetables well to remove any dirt, do not let your children eat dirt, and discourage your pet from hunting.

And see your veterinarian for parasite testing and to discuss appropriate products for year round prevention and control of parasites in order to protect your pets and your family.

If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.


Roundworms: What Are They and Why They Are a Winter Risk For Your Dog

Roundworms are the most common intestinal parasite impacting companion dogs across the country, even dogs who are well cared for and receive regular veterinary care.

They live in a dog’s intestines and feed on the intestinal contents, are light brown or white and several inches long, and resemble spaghetti when in the dog’s intestines. Dogs with roundworms may show small bits of visible evidence of the worms in their poop or vomit.

Unfortunately, roundworms are incredibly common and are spread through dogs (and other animals) shedding the eggs through their feces. Other dogs then become infected by accidentally ingesting roundworm eggs while outside playing.

Dogs of any age from newborn puppies to adults can be impacted by roundworms. Companion Animal Parasite Council (CAPC) which tracks infection rates nationally noted that dog fecal samples across the United States showed that 30 percent of dogs younger than 6 months shed roundworm eggs making this an issue impacting dogs of all ages from puppies to adults. In addition, CAPC studies have found that positive cases of roundworm infection have been detected in dogs in all 50 states across the country.

Why roundworms are the risk in the winter

Dr. Craig Prior, BVSC, CVJ, the former president of the CAPC says that the council’s work on the mapping of roundworm is beginning to show a seasonal prevalence of roundworm. The CAPC releases a monthly update of US cities that have the highest positive percentage increase of roundworms. Bookmark the monthly study (here) to check for updates.

Unlike many other parasites, roundworms are not susceptible to temperature changes, because as Dr. Prior explains “roundworm eggs have a strong protective layer, they are not sensitive to extreme temperatures and can survive in the environment for months — and even years.”

This means our dogs can be susceptible to infection from roundworms year-round, and the risk does not decrease in winter months regardless of where in the country you live.

Curious about roundworm risks in your local area? CAPC parasite prevalence maps give a roundworm prevalence breakdown for every county in the United States.

A small pack of dogs play at a public, off-leash dog park. Photo: Darwin Brandis/ Getty Images

How to prevent roundworms in dogs

The most important thing you can do to protect your dog from roundworm is to keep areas where your dog spends time clean and to not allow your dog to spend time in parks or areas where dog feces are allowed to buildup. Dog waste is one of the primary causes of roundworm spread. All dog parents can help prevent the spread of roundworms by immediately picking up feces when walking our dogs in public areas and regularly from our backyards.

Unfortunately, CAPC has discovered that 27% of fecal samples collected in dog parks from across the country showed that roundworm was present. In response to the prevalence of roundworm, CAPC recommends that puppies be tested for roundworm at least four times in their first year of life. CAPC also recommends that adult dogs be tested at least twice a year and that dogs receive monthly broad-spectrum parasite preventative medication year-round.

What are the symptoms of roundworm in dogs?

Symptoms of roundworm infection in dogs include weight loss, diarrhea, dull coat, vomiting as well as a bloated/pot-bellied abdomens. If left untreated a roundworm infection can be fatal to dogs. Although at times you can see worms in your dog’s vomit or feces, the key way that you can check if your dog has roundworm is through a veterinary examination. “Your veterinarian can check your dog’s stool, be able to treat them if they are positive, and then put them on a preventive,” said Dr. Prior.

Roundworms are also a risk for humans.

Not only are roundworms dangerous for our dogs, they can also pose significant health risks for people. Humans generally become infected with roundworms from handling and then accidentally ingesting dirt that contains roundworm larva. Children are particularly at risk because they are likely to spend time playing outside and dirty soil is more likely to come in contact with their mouths. Another reason to wash those hands. Symptoms of roundworm infection in humans include fever, cough, abdominal pain, and in severe cases, roundworms can lead to respiratory failure or blindness.

Featured photo: chabybucko/Getty Images


What Are Roundworms?

Roundworms are intestinal parasites that are common in dogs.   These parasites are round, up to 7 inches long, and white to pale brown in color. They look a little like spaghetti noodles. The medical term for infection with roundworms is ascariasis. As we stated earlier, Toxocara canis is a the most common type of roundworm in dogs and is frequently seen in puppies it can also infect humans.


Because of this human risk, the Centers for Disease Control (CDC) recommends that all puppies and their mothers undergo deworming treatments, whether diagnosed with the parasite or not.   Your veterinarian can provide a dewormer that is safe and effective to use.

These precautions, along with simple sanitation procedures, will protect both puppies and human family members from roundworms. Clean up feces from the puppy's yard at least once a week, and prevent young children from playing in the dog's "toilet area."


Watch the video: Roundworms of Dogs and Cats - Plain and Simple (July 2021).