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Heartworm Information

Where are Heartworm and other diseases located?

Here is a link to a map showing the prevalence of Heartworm, Lyme, Ehrlichiosis and Anaplasmosis by our Lab service provider, Idexx (this map is based on actual test information for the last 5 years).  Please note the pockets of positive test results in the population centres correlate to where the tests are performed, not where the pet contracted the disease. To read more about Lyme disease in canines, click here.

Recommendations for South Western Ontario

The single recommendation that we have for all of our patients is yearly Heartworm testing. We can respect that some owners do not wish to use preventative medications on their pets or in the environment and yearly testing is the only way to catch Heartworm (HW) before it induces heart disease. HW testing is a blood test performed each spring. In Southwestern Ontario, our typical time frame of HW transmission lasts from mid-May until mid-October. It will then take six months after infection to show a positive on a HW Test. For this reason HW testing is typically done after April 15 to check for the previous year’s infection. Due to the increasing prevalence of Tick-borne diseases such as lyme, erlichia and anaplasma, HW testing is combined with testing for all three of these diseases as well (4Dx). For further information click here to read an article from Animal Wellness Magazine.

Wellness Testing

During HW season our lab partner puts on special pricing on their wellness profiles combined with insect-borne disease testing. This makes spring an ideal time to do annual or biannual wellness screening blood work on our pets to ensure early detection of changes in the blood work that may signal health concerns we wish to be proactive on.  It is especially important each year if your pet is in their senior years (over 8 years of age).  To find out what the different blood parameters mean, click here for our fact sheet.

Preventative options

If you are interested in HW prevention, there are many different options to choose from based on your lifestyle and family’s needs. Some preventions can help with flea and/or tick control as well. We can help you choose the prevention that best fits your needs and wants. In trying to support the body’s natural ability to heal itself while having to use compounded chemicals to protect it, we recommend using milk thistle for 1-2 weeks after each HW prevention dose to support the detoxifying of the liver. Milk thistle has an antioxidant effect and it has a protective and therapeutic effect against hepatotoxicity and can minimize damage when toxicity occurs. At the end of the season, we can also use a homeopathic detox program to help the body eliminate any residual toxins it was not able to successfully eliminate on its own.

Alternative Preventatives

There is a study that considers the use of Black Walnut Oil and Wormwood as a HW preventative. Please note that while this study was published in a well-regarded journal, it is of poor quality and does not prove that these supplements do in fact prevent HW infection.  They factually know that none of the study group contracted HW, but it is not known if any of these dogs were actually challenged by the parasite.  This may be a good protocol for some dogs that are not able to tolerate HW medications and whose owners would still like to try some form of protection.

The bottom Line

The overall message is that testing is our best chance to catch HW early.  Preventative medication combined with natural supplements to support the individual provides an integrative approach to veterinary medicine, thus allowing us to incorporate the best of both worlds.