Internal Parasites


The following list of internal parasites are common to dogs and cats worldwide. All may be transmitted to man through unsanitary living conditions. The exception to this would be Heartworms, which are not ordinarily transmitted to humans.

For more information on these or other infectious parasites, please contact your veterinarian.

A protozoan intestinal parasite, it is highly contagious. It is spread through the fecal-oral route . The common symptoms are diarrhea, often with blood and mucous, dehydration, and weight loss. Sanitation is very important in controlling this disease. Prompt removal of fecal matter can reduce the re-contamination of animals. Avoid feeding raw meat to your pet, as this is also a source of infection. It is treated with sulfa drugs prescribed by your veterinarian.

This is common in areas at sea level, the tropics and all mosquito-infested areas, particularly the Atlantic Coast and the Southeast. Clinical signs are seen primarily in dogs, although cats and ferrets are susceptible to infection. The most common symptoms are coughing, decreased exercise tolerance, and weight loss. The diagnosis is only possible with a blood test to determine the presence of microfilaria in the bloodstream. This test is performed by a veterinarian.

The best form of control is prevention. A prescription from your veterinarian is necessary, and started early enough can reduce the possibility of the worms reaching the heart and growing into adults. In our area year round treatment is necessary. The treatment of cats and ferrets is controversial at this stage. Please consult with your veterinarian on the best treatment for your pet. Do not give any heartworm preventative to an animal that has not been tested by a veterinarian. If the animal has adult worms in the heart the medicine can cause the animals death!

This worm is highly contagious and is also transmitted by the fecal-oral route. Although they can be transmitted through the skin by contact with contaminated feces, such as through the feet of pups and humans. Mother dogs can pass them through their milk to the pups as well.

Common symptoms are diarrhea, usually with blood, weakness , anemia, and occasionally coughing. It can be fatal in young animals, and sometimes in adults if left untreated for long periods. Treatment is with various medications prescribed by your veterinarian.


There are several types of roundworm. They are highly contagious and are spread through the fecal-oral route. Most puppies and kittens are born with them. Part of the life cycle of roundworms involves migration through the lungs of the host.

Common symptoms are diarrhea, sometimes with blood, a distended abdomen, and occasionally coughing or vomiting of adult worms. There is a high mortality in young animals, and less in adults. It is treated with various medications prescribed by your veterinarian.

These worms are less serious than others, but can have detrimental effects on your pet. They are spread fleas and the ingestion of raw meat. Fleas carry the tapeworm larvae. Animals that run loose become infected by eating carrion or small animals they kill.

Confined animals are more commonly infected by fleas. Symptoms are less noticeable but include, weight loss, irritability, constant appetite, shaggy coat, colic, mild diarrhea, and if left untreated for an extended period may result in emaciation, and seizures. Effective treatment must be prescribed by your veterinarian.

A highly contagious infectious worm, it lives in moist areas, and when an infected animal passes eggs in the feces these eggs may survive the environment for up to 5 years. It is transmitted by the fecal oral route.

Common symptoms are sporadic diarrhea, sometimes with blood, chronic weight loss, and sometimes anemia. The incubation is 3 to 12 weeks, and may remain in the system for up to 16 months. Treatment is prescribed and administered by your veterinarian.