Prevention Takes the Bite Out of Heartworm Disease

Dr. Drew Sullivan poses with Oskee

Throughout this time of quarantine, I have been spending more time outside, as I am sure many of you have, too. Besides the overabundance of cicadas in my neighborhood, currently there seems to be a plethora of mosquitoes looking for a blood meal. Just as we love summer in Chicago, so do mosquitoes. Summer is the time for peak transmission of heartworm disease across the U.S. Heartworm disease is considered endemic in Illinois, and according to the American Heartworm Association, clinics in the Chicago area see an average of 25+ cases per year.

2019 Heartworm Incidence map
Visit the American Heartworm Society website to see how heartworm cases have spread and increased across the country over the past 18 years.

As I sit outside, I think how lucky I am because mosquitoes don’t seem to like me; my wife is not so lucky. Then I wonder if my dog, Oskee, is getting bit as much as we are? And is he getting infected with heartworms?

Screen capture from video about heartworm prevention
Watch a short video about the life cycle of heartworms and how preventive medication works when given every month.

The importance of prevention makes so much sense once you have a little knowledge about the disease process and how monthly preventive medication works. As described in this short video, the monthly preventive does NOT prevent exposure, but kills off any immature baby heartworms already present in your dog. If the preventives are not given every 30 days, the immature heartworms can mature to juvenile worms before the next dose, thus resulting in heartworm disease.

If you miss a dose or are late giving a dose, give the dose as soon as you remember. While uncommon, an infection may develop within your dog from a single missed dose. Multiple missed doses, especially during peak transmission months, puts your dog at high risk of infection.

The heartworm test performed at annual wellness visits screens for adult heartworms. It takes 6 to 7 months after infection for the heartworms to mature into the life stage detected by the heartworm test. Therefore, if you miss a dose, start up prevention as soon as possible. Then have your dog tested within the next year to be sure that infection did not occur during the unprotected period.

For less than $10/month your pet can be protected. While there is a treatment for heartworm disease, it is more expensive and more painful than monthly prevention. The average cost of treatment for a medium-sized dog is $1,500 vs. $10/month for prevention.

If your dog is not currently on prevention or you need a refill, give us a call today. If you have questions about the different preventive medications on the market, please reach out as we would be happy to discuss your questions and concerns.

—Dr. Drew Sullivan