How do Tapeworms affect your dog?
The most common tapeworm of
dogs (and cats) is called Dipylidium caninum. This parasite
attaches to the small intestinal wall by hook-like mouthparts. Adult
tapeworms may reach 8 inches (20 cm) in length. The adult worm is
actually made up of many small segments about 1/8 inch (3 mm) long. As
the tail end of the worm matures, the terminal segments break off and
pass into the stool. Occasionally, the mobile segments can be seen
crawling near the anus or on the surface of a fresh bowel movement.
These segments look like grains of rice and contain tapeworm eggs; the
eggs are released into the environment when the segment dries. The dried
segments are small (about 1/16", or 2 mm), hard and golden in color.
These dried segments can sometimes be seen stuck to the hair around the
commonly found tapeworm, called Echinococcus, also occurs in
How did my dog
In order for a dog to become
infected with the common tapeworm, Dipylidium, the dog must
swallow a flea that contains tapeworm eggs. This process begins when
tapeworm eggs are swallowed by flea larvae (an immature stage of the
flea). Contact between flea larvae and tapeworm eggs is thought to occur
most frequently in contaminated bedding or carpet. Next, the dog chews
or licks its skin as a flea bites; the flea is then swallowed. As the
flea is digested within the dog’s intestine, the tapeworm hatches and
anchors itself to the intestinal lining.
become infected with Echinococcus when it eats a small mammal,
usually a rodent, that contains the worm. Foxes and coyotes (and the
wild rodents upon which they prey) are important in the life cycle of
this parasite. Dogs and cats may also become infected if they eat
rodents carrying the parasite.
What kind of
problems do tapeworms cause for the dog?
Tapeworms are not highly
pathogenic (harmful) to your dog. They may cause debilitation and weight
loss when they occur in large numbers. Sometimes, the dog will scoot or
drag its anus across the ground or carpet because the segments are
irritating to the skin in this area. The adult worm is generally not
seen, but the white segments which break away from the tapeworm and pass
outside the body rarely fail to get an owner's attention!
Occasionally, a tapeworm will release its attachment in the intestines
and move into the stomach. This irritates the stomach, causing the dog
to vomit the worm. When this happens, a worm several inches in length
will be seen.
tapeworm infection diagnosed?
An infection with
Dipylidium is usually diagnosed when the white, mobile segments are
seen crawling on your dog or in the stool. Tapeworms are not usually
detected by the routine fecal examination performed by the veterinarian.
Because of this, veterinarians depend on the owner to notify them of
possible tapeworm infection in the dog.
Echinococcus infections are harder to diagnose than the tapeworm
caused by fleas because the segments are small and not readily seen.
How are the tapeworms
Treatment is simple and,
fortunately, very effective. A drug which kills tapeworms is given,
either orally or by injection. It causes the tapeworm to dissolve within
the intestines. Since the worm is usually digested before it passes, it
is not visible in your dog's stool. These drugs should not cause
vomiting, diarrhea, or any other adverse side-effects.
fleas is very important in the management and prevention of tapeworm
infection. Flea control involves treatment of your dog, the indoor
environment and the outdoor environment where the dog resides. If the
dog lives in a flea-infested environment, reinfection with tapeworms may
occur in as little as two weeks. Because the medication which treats
tapeworm infection is so effective, return of the tapeworms is almost
always due to reinfection from the environment.
How do I tell
tapeworms from pinworms?
Tapeworms and pinworms look
very similar. However, contrary to popular belief, pinworms do not
infect dogs or cats. Any worm segments seen associated with dogs are due
to tapeworms. Children who get pinworms do not get them from dogs or
tapeworms infectious to people?
Yes, although infection is not common or likely. A flea must be ingested
for humans to become infected with the most common tapeworm of dogs.
Most reported cases have involved children. The most effective way to
prevent human infection is through aggressive, thorough flea control.
The risk for infection with this tapeworm in humans is quite small but
Echinococcus tapeworms are of more concern. These tapeworms cause
very serious disease when humans become infected. Hunters and trappers
in the north central United States and south central Canada may be at
risk for infection by this worm if strict hygiene is not observed.
Rodent control and good hygiene are important in preventing the spread
of this disease to humans. As with the more common tapeworm, infection
with Echinococcus is infrequent but possible.
What can be done to control tapeworm infection in
dogs and to prevent human infection?
Effective flea control is important.
Prompt deworming should be given when parasites are detected;
periodic deworming may be appropriate for pets at high risk for
All pet feces should be disposed of promptly, especially in yards,
playgrounds, and public parks.
hygiene is important, especially for children. Do not allow children
to play in potentially contaminated environments.