Many parasites have the ability to infect dogs and cats, with puppies and kittens being most susceptible. Intestinal parasites include the common roundworms and hookworms, but puppies and kittens may also be infected with coccidia and giardia.  Puppies can also contract whipworms.  Intestinal parasites may cause weight loss, diarrhea, blood loss, and vomiting, although many pets may seem healthy with only intermittent gastrointestinal signs. External parasites include fleas, ear and skin mites, lice and ticks.

Heartworm disease (affecting mainly dogs, but can affect cats in rare circumstances) is caused by a parasite transmitted by mosquitoes and infects the arteries leading from the pet’s heart to the lungs. Serious infections can cause exercise intolerance, a chronic cough, heart failure and death. In Ontario, over 300 cases occur each year, with most in southern and southwestern Ontario, but cases also occur in dogs that have never travelled outside of the Ottawa Valley.

Roundworms have a particularly stubborn lifecycle in dogs and cats. The microscopic eggs hatch following ingestion, and the larvae burrow through the intestinal wall and travel through body tissues for a period of time. Eventually, these tiny parasites emerge back into the intestines, grow into adult spaghetti-like worms and breed releasing thousands of eggs back into the environment.

De-wormers only work in the gut, so we continue to administer them every two weeks until the puppy/kitten is three months of age, then once a month until the puppy/kitten is six months of age, as the larvae emerge back into the intestine.

Fleas can be a problem at any time of the year if your pet meets another animal with fleas. Adult fleas spend their entire lifecycle on the animal, but will lay 20 to 30 eggs a day following a blood meal. The eggs fall off the dog and lodge in cracks and crevices, around baseboards and outdoors. Within several weeks, if the conditions are right, the eggs will hatch into larvae, transform into pupae and eventually emerge as young adults looking for a warm pet to call their own.

Fleas can cause intense itching, skin diseases and can even transmit diseases. In our region, most flea problems peak in late summer and fall as the number of eggs builds up in the environment.

Currently, we can prevent many intestinal parasites, fleas, and heartworm with safe and effective medications administered once a month. Having a stool sample checked once to twice yearly allows us to identify parasites before they become a problem.

Some parasites can also infect people, especially children and those with lowered immune systems. For a great resource on parasites, pets and pet ownership, see the Worms and Germs Blog.

We can recommend a parasite-control program for your dog or cat that matches your pet’s lifestyle and circumstances.