The Insane Heartworm Life Cycle in Dogs

The heartworm life cycle in dogs is a long journey from mosquito bite to a heart chamber full of foot-long worms.  Mosquitoes for you and I are mostly just a nuisance. Sure, they can carry some pretty nasty disease, but if you live in North America, that’s pretty rare. 

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Dogs, however, are vulnerable to heartworm. The heartworm life cycle in dogs is long and never-ending unless your dog is treated with prescription medication.

Keep reading to get some perspective on how important it really is to get rid of these parasites.

If you live in an hot, humid area where mosquitoes are endemic, it’s really important to have your pets protected against heartworm.  It’s a relatively small but important investment for the health and safety of your dog(s). 

How Do Dogs Contract Heartworm?

Dog contract heartworms through the bite of an infected mosquito. The larvae are transmitted through the saliva of the mosquito which then make their way through the dog’s bloodstream. 

Heartworms can grow to be a foot long. They live inside your dog’s heart, lungs, and blood vessels, often with little signs or symptoms in the early stages.  Early on, you might notice an occasional cough without realizing there is a bigger problem brewing inside.

Watch the following Youtube video to get a better sense of heartworm disease in dogs

Dogs are a natural host for heartworms, but they also thrive in the bodies of other mammals.  For example, wolves, coyotes, foxes, and others are prone to this parasite.

There Must be SOME Signs or Symptoms!

It can take heartworms up to six months to really start showing signs in your dog. At that point, coughing may be more pronounced and you might notice weight loss. Your normally active dog suddenly stops playing and may not have an appetite. 

As the worms grow, your dog may become tired easily and unable to play like he/she used to. The reason for that is because heartworm infections slowly destroy the heart muscle and arteries leading to the lungs.

As these organs waste away, it’s harder and harder for your dog to get the oxygen needed for energy. 

Read about heartworm prevention written by the American Heartworm Society.

What Can I Do? 

If you haven’t started a monthly heartworm preventative yet, don’t panic. As long as your dog still appears healthy, you can start a program immediately.

The first thing you want to do is get your dog to a veterinarian.  Yes, there are over-the-counter worm medications for dogs, but most only cover the basics (roundworm, whipworm, hookworm). 

In order to successfully get rid of a heartworm infection, you’re going to have to keep your dog on a continuous, year-round treatment plan.  

Why Does the Treatment Have to be Year-Long?

Treating heartworms in dogs is a long process.  Medications might kill the mature adult worm, but it will do nothing to the growing larvae waiting for their chance to thrive.

The only way to adequately treat heartworms in dogs is to give them a continuous treatment through the whole year. 

Keep in mind that this might depend on where you live.  I live in an area in eastern Canada where the temperatures are only hot and mild a few months out of the year. 

However, if you live anywhere in the southern US, where temperatures are warm enough year-round, you’re going to want to protect your dog.d

A Few Months of Treatment Doesn’t do the Trick!

The reason it takes so long to treat heartworm is because of the parasite’s life cycle. It takes six months for the parasite to mature from larvae to adult and by then, your dog may have been re-infected with further mosquito bites. 

Heartworms can actually live inside your dog for up to 7 years! Every time your dog is bitten by a mosquito, a whole new heartworm life cycle is started.

By giving regular, continuous heartworm medications, you can be sure to get the entire infestation while stopping further ones from taking hold.

Heartworms can actually live inside your dog for up to 7 years! Every time your dog is bitten by a mosquito, a whole new heartworm life cycle is started. By giving regular, continuous heartworm medications, you can be sure to get the entire infestation while stopping further ones from taking hold.

Are Heartworm Medications Safe for my Dog?

Federally approved heartworm medications that are prescribed by a licensed veterinarian are safe.

All medications (whether it’s our own prescriptions or prescriptions for our dogs) carry risk of side-effects. Generally speaking, these side-effects are usually mild and are not nearly as dangerous as the infestation. 

Let’s face it, heartworms kill dogs.  Dogs who’ve been rescued from the streets are often loaded with heartworms.

Unfortunately, many of these dogs are already in the danger zone when they’re found.  Once a dog has heartworms, the parasites continue to grow and multiply. Without treatment, they cause the cardiovascular system to stop working, resulting in death. 

Let’s face it, heartworms kill dogs.  Dogs who’ve been rescued from the streets are often loaded with heartworms. Unfortunately, many of these dogs are already in the danger zone when they’re found.  Once a dog has heartworms, the parasites continue to grow and multiply. Without treatment, they cause the cardiovascular system to stop working, resulting in death. 

Avoiding the Deadly Caval Syndrome

Once a dog is in the stages of cardiovascular collapse, he/she is in what’s known as “caval syndrome”. This is a life-threatening emergency.  The signs and symptoms of caval syndrome in dogs includes heavy breathing, pale gums, dark bloody urine.  If the dog has reached this critical point, chances of survival are slim. 

Do I Live in A Heartworm Endemic Region?

Look at maps from 2013 onwards and you’ll notice that the areas of endemic mosquito populations are rising. The heaviest population of larvae-carrying mosquitoes is in the southern and eastern parts of the United States and Canada. 

To get a better idea of where heartworm is highest, take a look at these maps. 

There MUST be Natural Ways to Get Rid of Heartworm in Dogs!

No matter what anybody tells you, homeopathic options are not the way to go.  Alternative or all natural worming methods have existed for centuries and, in some cases, they have shown to be a least partially effective.  

Heartworms, however, don’t live in the digestive system where something like diatomaceous earth could potentially aid in killing parasites.  They don’t live in the dog’s fur or in the uppermost layers of skin either. There is no way for a natural remedy to penetrate the heart muscle and arteries. 

Trifexis for Dogs 

Specialized medicines like Trifexis, for example, have been tested and proven successful in ridding dogs of heartworm infestation.  However, as stated above, it will only work with continual treatment. Even if you successfully treat one infestation, your dog will surely succumb to another one, especially if he/she lives in a region prone to the parasitic infection.

Is My Family At Risk of Contracting Heartworm?

Mosquitoes carry a wide number of pathogens that can be passed on to humans. These pathogens include bubonic plague and dengue fever (in sub-tropical regions). 

Read this post by the Minnesota Department of Health to get a better idea of the reach mosquitoes have in terms of disease transmission. 

You might not hear about travellers being infected with bubonic plague these days, but I’ll bet you’ve heard of the zika virus, malaria, yellow fever, and west nile. 

In dogs, however, your biggest worry should be the transmission of heartworm. The best way to prevent transmission of heartworm in dogs is to keep them regularly treated with prescription medication.

I’m Afraid to Give My Dog Trifexis

It’s no wonder! Look around the Internet and you’ll find countless fear mongering and anecdotal stories that  probably have no bearing on the safety of drugs like Trifexis. 

The truth is, dogs who’ve died while on Trifexis could have been suffering from underlying conditions before starting the medication. It’s up to the veterinarian to make sure your dog has no other pre-existing conditions before prescribing Trifexis. 

Yes, there is a risk of seizure in dogs who take Trifexis, but (believe it or not) occasional mild seizures are not something to worry about. If your dog has chronic seizures because of epilepsy, the veterinarian might want to prescribe another type of drug.

There are countless worming drugs on the market. However, veterinarians are now starting to notice a decline in the efficiency of old-school deworming medication.  Like bacterium, the worms seems to be developing a resistance to these drugs. 

So What’s the Solution?

It’s really important to get on top of the heartworm life cycle in dogs with an oral or topical solution prescribed by a licensed veterinarian. Anyone who loves their dogs worries about side-effects, so talk to the doctor and ask questions.  Every medication has side-effects, even that Tylenol you take has side effects. Try to remember that the heartworm life cycle is much riskier than FDA approved meds. 

At the end of the day, you dog’s safety is on the line. By administering regular doses of an approved drug, you can keep your dog happy and healthy for years to come. 

My goal of this post was to help you make an informed choice free from the hysteria you may read or hear. It’s very sad when a dog passes away, no matter what the reason. However, please remember that people who are grieving often are also very angry. It’s easy to place the blame somewhere and, sometimes, that blame is on a prescription drug. 

It’s possible that certain drugs are responsible for serious adverse effects. However, a licensed veterinarian should be trusted to make the best choice for your dog’s needs. The veterinarian will base the decision on your dog’s age and current state of health. Regular appointments to monitor your dog’s condition will go a very long way in avoiding serious complications (if any). 

Summary

I hope you were able to get some useful information from this post and I welcome your thoughts on the topic.  I realize this is very controversial for many, but thought it was important to state the truth as I see it. Please feel free to comment below or contact me directly at latheriault@hugspetproducts.com 

Remember…I am not a veterinarian. I do my research carefully and aim to provide good quality resources free from hype.  

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the insane heartworm life cycle in dogs
Goofy dog running away from murderous mosquitoes!
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About Lisa Theriault

Lisa Theriault wants you to know right up front that she is not a veterinarian. None of the articles/posts on this website are meant to take the place of veterinarian care.That said, Lisa has had a lifetime of experience dealing with dogs and plans on further education on dog anatomy and canine massage. In the meantime, Lisa's posts are all professionally researched and carefully crafted. The last thing she wants is to do or say anything that would hurt your dog.Stay tuned for more updates to Lisa's bio.