What Causes Heartworm in Dogs?

Angela Vuckovic
by Angela Vuckovic

One of the most dangerous threats to the health of dogs around the world is the dreaded  heartworm. Most people are not even aware of the illness, until it is too late for  treatment and the damage has already been done. In fact, many dog owners are not at all familiar with heartworm, how it occurs, how it progresses, and what causes it in the first place. That’s why we’ll go into all of the details every dog owner should know about heartworm. 

What Is Heartworm Disease in Dogs and What Causes It?

Heartworm disease in dogs is caused by a parasitic worm, called Dirofilaria Immitis. These are most simply put, heartworm larvae, and are carried within mosquitos. And that’s how they are transmitted – through the bite of an infected mosquito. When a mosquito, carrying a heartworm larva, bites a dog, it immediately transmits the larvae onto the dog’s skin. This is how the heartworm enters the bloodstream, through the teeny tiny mosquito bite wound – yes, that is how incredibly small these larvae are. After this, over the course of several months, the deposited larvae mature and grow into adult worms that nest and reside within your dog’s heart, blood vessels, and lungs. 

Once they become adults and enter the animal’s system, these worms can really cause substantial damage to the lungs, heart, and even other organs. This damage is then manifested through visible symptoms, such as fatigue, weight loss, difficulty breathing, coughing, and – in the most extreme cases – heart failure. Heartworm needs to be treated. Otherwise, this disease can be fatal to dogs. Of course, your most common precaution is through regular use of heartworm preventatives, as well as minimizing exposure to mosquitoes or mosquito-dense areas. This can help protect your doggo from contracting a potentially deadly disease. 

Preventing And Treating Heartworm Disease in Dogs

This being said, we need to take into account that heartworm disease won’t be common in all parts of the world equally. The disease is prevalent in parts of the world with warm or humid climates, and high populations of mosquitoes. This is not an exclusive rule, however, and the disease can occur in all parts of the world, including temperate zones. As a diligent dog owner, you should get familiar with your region and if needed, take precautionary measures. If you live in an area where there are a lot of mosquitoes, you can invest in things like mosquito repellents for dogs. 

This innovative insect-repelling t-shirt can do wonders to keep the pesky biters at bay as it is made from a unique fabric that’s coated with permethrin, which is an invisible, odorless, and effective insect-repellent. Fun fact – US army uniforms contain the same technology to keep bugs away from soldiers, so you know it works!

You can also opt for  the classic mosquito repelling collar, which also works great if your pet is not one to paw their collar or doesn’t have sensitive skin that would mind direct contact with insect-repelling chemicals – they are safe for dogs but can be a bit harsh on mild skin.

Of course, the best way to protect your dog from heartworm disease is prevention. This involves using a monthly heartworm preventative that is usually prescribed by your veterinarian. You should not give your dog anything of your own accord but instead, consult a vet first. Either way, these preventatives are administered orally or topically, and they work by killing the harmful heartworm larvae before they mature into adult worms and cause damage. Besides this, you can prevent the onset of the disease in other ways too. Minimize your pet’s exposure to mosquitoes and areas that are full of them. For example, if it is summer, and you’d like to take a walk by the river, think again – these areas can be swarming with the buzzers. Not only that, but you should also ensure your pet gets regular vet checkups, which are crucial for ensuring that your pet is always healthy and that all preventive measures are up to date!

Angela Vuckovic
Angela Vuckovic

A proud mama to seven dogs and ten cats, Angela spends her days writing for her fellow pet parents and pampering her furballs, all of whom are rescues. When she's not gushing over her adorable cats or playing with her dogs, she can be found curled up with a good fantasy book.

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