Tapeworm Symptoms, Transmission and Prevention

Tapeworm, artwork
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Tapeworms are a ribbon-like flatworm that are parasites that live in the intestines of puppies. There are several varieties, but Dipylidium caninum is seen most often in cats and dogs.

While tapeworms are rarely a serious health risk, they can pose nutritional problems interfering with the puppy food your baby dog eats or other serious health risks. It’s important to understand how your puppy contracts tapeworms to know how to get rid of the parasite and prevent its return.

Tapeworms and Fleas

Immature worms must spend developmental time inside an intermediary host before being able to infest your puppy. The flea serves this purpose. If your puppy is infested with fleas, she is also highly likely to have tapeworms. That's why the incidence of tapeworms closely parallels the summer months of flea season.

Tapeworm eggs are eaten by the flea larvae, which then develops as the flea itself matures. When a pet nibbles to relieve that itch, she often swallows the flea and infects herself with tapeworm.

Description of Tapeworms

The head of the tapeworm, called the scolex or holdfast, is equipped with hooks and suckers that are used to anchor itself to the wall of the small intestine. There is no mouth as such; in fact, tapeworms don't even have a digestive system. Instead, nutrients are absorbed through their segmented body.

Called proglottids, these segments are linked together like a chain.

The parasite continuously grows new segments that are added from the neck down. Adult worms continue to add segments as long as they live, sometimes attaining lengths of two feet or more composed of hundreds of segments. Can you imagine several two-foot-long tapeworms inside your little puppy? That gives you an idea about the potential for problems.

Each proglottid contains both male and female reproductive organs. When mature, the segment produces up to 200 eggs. Segments furthest from the scolex are most mature, and once "ripe" they are shed from the worm's body, and pass in the puppy's feces.

Signs of Tapeworm

Once outside the body, each segment can move independently like tiny inchworms, but when dry they look like grains of rice. Infested pups typically have segments stuck to the hair surrounding the anal area, or in their bedding. Eventually, the segments dry and rupture, releasing the eggs they contain into the environment. The life cycle is complete in two to four weeks.

Tapeworm eggs are passed and shed so sporadically, that your veterinarian examining the pup's stool for telltale evidence may often be inconclusive. It's considered diagnostic to find the segments on the pet.

Tapeworm Health Risks

Tapeworms are rarely a medical problem and are usually considered an unpleasant annoyance. The moving proglottids may cause irritation to the anal region, which may prompt puppies to excessively lick themselves or "scoot" their rear against the floor or ground.

Without treatment, however, massive tapeworm infestations potentially interfere with digesting food and/or elimination.

Puppies may suffer intestinal blockage should too many worms become suspended the length of the intestinal tract.

Also, the hooks of the holdfast can damage the intestinal wall. Diarrhea with mucus and occasionally blood may be signs of tapeworm infestation. Long-term infestation can result in an unkempt, dry-looking coat and generally unhealthy appearance, and reduced energy.

Flea tapeworms are the most common kind of cestodes affecting dogs. However, other species may be contracted if the dog eats wild animals like mice or rabbits. When I was a child, our first Sheltie came from a backyard breeder (yes, we didn’t know any better) and was diagnosed with rabbit tapeworms that took forever to eliminate!

Human Health Risk

There's a human health risk associated with two species of tapeworms which dogs may expose people to if they eat the host animal.

Echinococcus granulosis also can be found in sheep, cattle, goats and pigs and is found in Utah, California, Arizona and New Mexico and most cases in people go unnoticed. But Echinococcus multilocularis affects foxes, coyotes and rodents indigenous to Alaska, the Dakotas and surrounding North Central states, although human infections are rare, they can be deadly. Both may cause parasitic tumors in the liver, lungs, and brain of infected people. Check with your veterinarian to see if these types of tapeworms pose a risk in your neck of the woods.

There are several safe and highly effective treatments for tapeworms, which may be administered either as a pill or injection. Unless constantly exposed to reinfestation by fleas, a one-dose treatment will eliminate the tapeworms. Controlling fleas is the best way to prevent tapeworm infestation.