Parasite Prevention

What is Heartworm and how can your pet get it?

Heartworm, or Dirofilaria immitis, is a blood borne parasite that is transmitted through the bite of a mosquito.

Mosquitoes ingest the infective larvae (or microfilariae) from a heartworm positive animal and transfers it to another animal. The microfilariae then travels through the bloodstream until it matures into an adult. The adults reside in the pulmonary artery and the heart, hence the name heartworm. This whole process, from larvae to adult, takes 6 months. A heartworm infection is very serious and can lead to many complications, such as death. This is due to where the adults reside and reproduce. They can cause pet's to develop congestive heart failure and not be able to pump blood through their body as efficiently. 

Heartworm is more prevalent in dogs, however it is possible for cats to get heartworm as well. The signs of an adult heartworm infection are similar to those with heart issues: lethargy, weakness, intolerance of exercise, weight loss, coughing etc. However, when the infection is just in the microfilariae stage, there are no symptoms of this parasitic infection.

A simple blood test allows us to detect heartworm antigens (a substance that is produced by the heartworm that interacts with the immune system) in the blood. This should be done every spring, even if your dog has been on heartworm prevention the previous season.

Prevention is the best option when it comes to heartworm. Treatment for a heartworm infection is very costly (a couple thousand dollars) and painful (needs to be deep intramuscular injections) for the animal. Whereas, the average heartworm prevention medication costs between $45-90 (depending on your pet's weight) for 6 months worth. For more on what prevention option are available, look in the next tab.

Fecal Testing: What are we looking for?

The main way we diagnose a parasitic infection is via fecal testing. We collect a small sample of feces and send it to the lab, where they can perform variety of tests to determine if a pet has parasites and which parasite(s) they are. 

There are a variety of parasites that cats and dogs can get, such as roundworms, hookworms, etc. Many of these parasites are transmitted through ingestion of the egg in the feces from an infected animal. The eggs than hatch and mature in your pet, eventually passing eggs and continuing the cycle. 

Most parasites are easily treated with dewormers, such as Panacur or Strongid-T. Sometimes multiple doses are needed to fully clear the adult parasites and eggs from a pet, therefore we recommend re-running a fecal test after completion of the dewormer to make sure all the parasites are gone.

If you have any questions about the type of parasites your pet can pick up or about fecal testing, give us a call or book an appointment with one of our veterinarians/RVTs and they would be happy to help.

Heartworm Prevention

There are a few options when it comes to protecting your pets against heartworm. There are oral products as well as spot on products. Both need to be given once a month from June to Nov. A blood test needs to be done on any pet older than 6 months before giving heartworm prevention products. This is due to the fact that the medication to treat heartworm is a lot different than what is used to prevent it, as the preventions do not kill the adult parasites effectively.

There are pros and cons to both the oral and spot-on prevention medications:

  • Topicals do not get absorbed systemically and just say on the fatty layer of the skin
  • Orals are easy to give if your pet likes treats. Most are beef flavoured and dogs love them
  • If you have cats or small children, they need to be separated from the dog for a bit after the topical is applied. This is so the solution has time to dry & is not rubbed off onto another pet/child.
  • If your dog/cat, doesn't like swallowing pills/chews then the best option is topical prevention.
  • If you have a squirmy pet, putting a topical prevention medication might be difficult to do.

One of our veterinarians or veterinary technicians can go over all the options for you and find one that is the best fit for you and your pet.

Flea/Tick Prevention

With the warm weather, comes flea/tick season. Ticks become active around 4 degrees Celsius and require no thaw period. This means that as soon as it becomes warm out, they will become active and start searching for their next host, even if there is still snow on the ground. Fleas and ticks have slightly different life cycles however they both require actually biting the host and having a blood meal in order to develop. With this blood meal, they can transmit a variety of diseases as well as some parasites to their host (aka your pet!)

Some diseases/parasites that your pet can get from fleas/ticks:

  • Tapeworms - Dipylidium caninum are transmitted from fleas
  • Lyme disease
  • Erlichia
  • Rocky Mountain spotted fever

The best way to avoid your pet from developing these conditions are by prevention. Flea/tick prevention is similar to heartworm prevention as it is a once a month treatment and comes in either oral or topical forms (for the pros and cons of topical vs oral products, look under the heartworm prevention tab). Both products stop the flea and tick from transmitting the diseases, by killing them before they have a chance to take a blood meal.

Ticks have become more prevalent in the Markham/Unionville region in the past couple of years. It is highly recommended to do yearly 4Dx testing, which tests for heartworm, lyme disease and two other tick borne viruses. This allows you to make sure that your pet is in optimal health and to treat any conditions before they become life threatening.

If you suspect that your pet may have fleas or ticks, or you want more information, please contact us and our veterinary staff will be happy to examine your pet or talk to you about the best options for your pet.