Tapeworms live in the small intestines and vary from
less than an inch to several feet in length. The head of the worm fastens to
the wall of the gut by hooks and suckers. The body is composed of segments that
contain the egg packets. To cure tapeworm infection, the head must be
destroyed. If it is not, the worm will regenerate.
The body segments containing the eggs are passed in the feces. Fresh, moist
segments are about one-quarter inch (6 mm) long and are capable of moving.
Occasionally you may see them crawling through the fur near your dog’s anus. When dry, they
resemble kernels of rice. Some dogs experience anal itching from the
segments. Tapeworms will drain nutrition from your dog but not to the extent
that ascarids, hookworms, and whipworms
The itchy skin diseases in this table are characterized by
constant scratching, biting at the skin, and rubbing up against objects to
relieve the itch.
Allergic contact dermatitis: Same as contact
dermatitis, but rash may spread beyond the area of contact. Requires
repeated or continuous exposure to allergen (such as wearing a flea
atopy: Severe itching that occurs in young dogs and begins in late
summer and fall. Caused by seasonal pollens. Occurs in mixed breeds...
The common tapeworm of dogs is Dipylidium caninum. Fleas and
lice serve as intermediate hosts when they ingest the eggs. A dog must bite or
swallow an infected flea or louse to acquire the parasite. A human could also
acquire D. caninum if they accidentally swallow an infected flea.
Several species of Taenia, another type of tapeworm, parasitize dogs. Taenia
are acquired by eating infected rodents, rabbits, and sheep. Diphyllobothrium
species are found encysted in the organs of fish. These tapeworms are found in
the northern United States and Canada.
Echinococcus tapeworms are uncommon in dogs. Intermediate hosts are deer,
elk, goats, sheep, cattle, swine, horses, and some rodents.
Treatment: Droncit, Cestex, Drontal Plus, Telmintic, and Vercom Paste are
highly effective against all the common dog tapeworms. Use them under
Prevention: The common dog tapeworm can be controlled by eliminating fleas
and lice from the environment. Dogs should be confined to prevent them from
roaming and eating dead animals. Avoid feeding your dog uncooked meat and raw
Public health considerations: Echinococcus granulosa and Echinococcus
multiocularis are significant public health problems. Dogs and humans can
acquire the infection from eating contaminated uncooked meat, and, in the case
of dogs, by feeding on the carcass of an infected animal. Humans can also
acquire the disease by ingesting eggs passed in the feces of dogs. Since humans
are not the definitive host, adult worms do not develop.
Instead, the larvae produce large cysts in the liver,
lungs, and brain. These cysts are called hydatids, and they can cause serious
illness and even death.
Echinococcus granulosus is found in the southern, western, and southwestern
United States-areas where sheep and cattle are common. Although dog-to-human
transmission is rare, a number of human cases (presumably from eating uncooked
meat) are reported each year. If your dog runs free in a rural area where this
tapeworm could be a problem, ask your veterinarian to check her stool for
tapeworms twice a year. This species of tapeworm can be identified only after
the head has been recovered by effective deworming. Until a
definite diagnosis is made, a dog with a tapeworm that could be Echinococcus
must be handled with extreme care to avoid fecal contamination of hands and
WebMD Veterinary Reference from "Dog Owner's Home Veterinary Handbook"