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Rise in canine heartworm disease as population grows

By Chris Michlewicz

Most of the problems associated with Colorado’s population growth are apparent, like traffic congestion. One not-so-obvious issue effects our beloved pets.

The incidence of heartworm disease in dogs has increased in recent years as families and their canines move here from warmer climates where heartworm is more prevalent. Dogs arrive infected, and as the population of infected dogs grows, so does Colorado’s population of infected mosquitos, making transmission of the disease more likely, according to the Lone Tree Veterinary Medical Center, which classifies the disease as a “growing epidemic.”

The prevalence of heartworm disease in Colorado dogs increased a whopping 67.5% between 2013 and 2017. From 2014 to 2017, more than 114,000 dogs were brought into Colorado by more than 130 animal shelters and rescue organizations. This represented approximately 9.5% of the total estimated population of nearly 1.2 million dogs in Colorado in 2017, according to BioMed Central, a website that collects peer-reviewed journals and shares discoveries from research communities in science, technology, engineering and medicine.

Heartworms live in the heart, lungs and associated blood vessels of an infected animal. The disease is not contagious, meaning that a dog cannot catch the disease from being near an infected dog, but rather through the bite of a mosquito. Signs of progressed heartworm disease include occasional or persistent cough, trouble breathing and tiredness after mild activity.

There are simple and inexpensive steps that dog owners can take to avoid heartworm. The first is a heartworm checkup at the vet every spring using a blood test. Prevention is key, as treatment for infected dogs is expensive and can be toxic and cause serious complications, such as life-threatening blood clots in a dog’s lungs. Pups over the age of 7 months should be tested for heartworms before starting heartworm prevention, the FDA says.

Semi-annual injections and topicals are preventative options, and monthly chewable and non-chewable oral tablets are available. A year’s supply of heartworm prevention medication can cost between $35 and $80, depending on a dog’s weight.



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