Parasites: Tapeworm Infections Tapeworms live/target the intestines.

An Overview of Canine Tapeworm Infections

Tapeworms that infect canines belong to the Cestoda class of parasitic platyhelminthic worms which almost exclusively inhabit the intestinal tracts of vertebrate animals. The worms do attach themselves to the inner walls of the intestine, but do not suck blood in the same volume as do hookworms. As the worms mature they shed mobile segments that are then passed in the feces and may often be seen around the anus, on the dog’s coat, or in bedding. Though it is not among the most harmful of parasites, it is still important to minimize tapeworm infections in your companion animals, as they may be passed to other mammals and occasionally humans. Thankfully, modern medicine has provided us with a plethora of de-worming medications, so treatment and prevention of tapeworms is relatively simple and highly effective.

How might my dog become infected?

As previously mentioned, tapeworm eggs are passed anally within mobile segments from an infected dog. Once outside the body, these segments dry out and release their egg cargo. These eggs may then be eaten by flea larvae present on the dog or in the carpet or bedding of the dog’s environment. As a dog chews or licks in order to alleviate the itching caused by fleas, he often will swallow fleas themselves. If the flea has at any point consumed tapeworm eggs, these eggs will be released into the digestive system during the digestive process. As this happens, the eggs hatch and the new worms attach themselves to the intestinal lining to start the cycle anew.

How is a tapeworm infection diagnosed?

Because tapeworm infections often cause minimal problems, clinical symptoms may be slight or nonexistent. The most common cause for suspicion of tapeworm infection is the sighting of small segments on the dog’s coat, around the anus, in his bedding, or on carpet frequented by the dog. These segments resemble grains of rice when new but change color slightly and become golden as they dry. Segments may cause irritation and cause your dog to lick the anus excessively or scoot across the floor in an effort to alleviate the irritation. Occasionally a tapeworm will release its attachment to the intestinal wall and move into the stomach, causing digestive upset and resulting in and episode of vomiting. The 5 to 8 inch long worm may sometimes be observed in vomit.

Though clinical symptoms are not common, especially severe tapeworm infestations may cause debilitation and weight loss if left untreated.

Once suspicion has been established, laboratory diagnosis is quite simple. Your veterinarian will examine a stool sample under the microscope in search of characteristic eggs. If eggs are detected, treatment can begin immediately.

What are the treatment options for dogs infected with tapeworms?

A number of very effective, very safe de-worming agents are available through your veterinarian. If your dog has been diagnosed as having an active infection of tapeworms, a drug which causes the worms to dissolve will be administered either orally or by injection.

Because fleas are an important vector in the transmission of tapeworms, flea control is an important part of eliminating tapeworm infections. There are numerous powders, collars, and topical treatments available. Consult your veterinarian for recommendations and more information.

Can canine hookworms infect humans?

Technically yes, but human infection is extremely rare and unlikely. An infected flea must be ingested for infection to occur.

What steps can I take to minimize the risk of infection for both my dog and myself?

Proper and effective flea control is of paramount importance. Once parasites have been detected, proper and thorough de-worming is necessary, and periodic de-worming may be indicated for dogs at a high risk of infection. Consult your veterinarian if you think you dog may fall into this category.

As is the case with all parasite prevention programs, proper hygiene is vital. All pet feces should be disposed of promptly, especially in yards, playgrounds, and public parks. Practices such as frequent hand washing should be encouraged, and children should not be allowed to play in potentially contaminated environments.

Additional resources on the web: Centers for Disease Control Fact sheet of commonly asked questions about tapeworm infections. Centers for Disease Control Provides information on the tapeworm life cycle, clinical features, diagnosis, and treatment in humans and animals. Merck Veterinary Manual Concise clinical overview of tapeworm infection in dogs and cats. International Veterinary Information Service Intestinal parasite reference guide for veterinarians.