Heartworm in Dogs

Heartworm in Dogs
May 27, 2019

Heartworm in Dogs


 You may have heard a lot about heartworm in dogs, but if you’re still unsure what heartworm can mean for your pets this article will work as a comprehensive guide. You’ll learn how to prevent your pet from catching heartworm, how to prevent the damage, and how heartworm can be treated. 

What is Heartworm? 


 Sadly, heartworm is a serious and potentially fatal disease which can affect all domestic animals. Heartworm is prevalent in the US and many other countries all over the world. The types of mammal which your dog can catch heartworm from include other dogs, ferrets, cats, coyotes, wolves, even sea lions. People can also be carriers of heartworm too! The most likely cause for infection – especially if you’re living in an urban area in America are coyotes and foxes. 

Heartworms are a form of parasite which can grow to a foot long. Despite the name, they don’t only affect the heart. They can live in the lungs and cardiovascular blood vessels as well as the heart. This can potentially lead to secondary conditions such as heart failure and lung disease. Yet, heartworm has the potential to do damage to pretty much every vital organ. 

When a dog suffers from a parasitic infection of heartworm the heartworms will produce offspring and lead to more heartworms in their bodies. It is very rare, but not unheard of for a dog to have up to several hundred heartworms with an infection. If your dog’s heartworm infection goes untreated for a long duration of time the dog’s quality of life and health will be severely affected. The news is even worse for cats as most cats do not survive when the worms are fully grown. 

How Can My Dog Catch Heartworm? 


 There are multiple ways in which your dog can catch heartworm. Mostly, we have the mosquito to blame as they play a pivotal role in the life cycle of the heartworm. 

If a mosquito feeds from an infected animal, they will get a blood meal which comes complete with baby heartworms. These worms are microscopic in size and they will turn into infective larvae in ten to fourteen days. 

When the infected mosquito goes looking for their next blood meal from a cat, dog, wolf, or coyote when they break the skin of the animal to feed, they will deposit infective larvae into the open wound. Then, it will take around 6 months before the larvae mature into fully grown heartworm. The lifespan of heartworms is fairly long too, they can live anywhere up to seven years in dogs. The duration is significantly less in cats as they will only live for a maximum of three years. 

As you can imagine, a mosquito can lead to a significant number of infected mammals. You will never be able to 100% protect your dog from mosquito bites, so, to prevent heartworm, you will need to use preventative treatment. We’ll move onto that a little later, but first, we will tell you the best way to spot the warning signs. 

Symptoms of Heartworm in Dogs


Until the heartworms which your dog is infested with are fully matured, there will be no warning signs of heartworm in your dog. There isn’t even any evidence that juvenile heartworms do any damage to your pet. However, once they are fully grown, there is no telling what damage can be done to your pet. Here are the symptoms to look out for: 

  • A persistent yet potentially mild cough
  • Lethargy or a loss of interest in exercise 
  • A concerning amount of fatigue after exercise
  • Weight loss 
  • Decreased appetite.
  • Swollen stomach due to too much fluid retention 

One of the most dangerous aspects of heartworm is the potential for your dog to develop blockages in the blood flow. This can be a very sudden blockage; therefore, it can be incredibly life-threatening for dogs. Many owners aren’t able to get their dog the treatment that they need on time, eventually leading to a cardiovascular collapse, otherwise known as caval syndrome. Symptoms of this syndrome include pale gums, laboured breathing and very dark-coloured urine. 

What are the Chances of My Dog Catching Heartworm? 


 There are multiple factors involved in the chances of your dog catching heartworm, including your geographical location. You may have noticed that in some local areas the infections are more prevalent. Alternatively, the disease may have a worse impact on the community that you realise! 

Each year – thanks to the mosquito heartworm spread to new locations. If you think that one tint mosquito couldn’t get far, you’d be wrong. Mosquitos can be blown in the wind, especially when there is bad weather. You may or may not remember the events which followed hurricane Katrina when over 250,000 pets caught heartworm. Stray dogs and wild animals moving from location to location also has an impact on the spreading of heartworm. Heartworm has already been diagnosed in every single state of America, yet how prevalent it depends on many factors such as the climate, to how many carriers there are in the area. 

Heartworm Testing and Prevention 


 It is highly recommended that you not only use preventative treatment for heartworm ever 12 months, but you should also get your dog tested for heartworms too. It is an incredibly serious and progressive disease, so, the sooner you catch it, the better chance your dog will have a full recovery. Remember there are very few warning signs of heartworm in the early stages. 

The heartworm test will need to be carried out by your vet, all it takes is a small blood sample, which will then be examined to see if there are any heartworm proteins in the blood. Many vets carry out this practice from start to finish in their own surgeries, however, some vets may need to send the results off for testing. 

Heartworm prevention treatment should start at 7 months old. Your dog will not need to be tested before this treatment, as the tests will be inaccurate. The heartworm proteins need 6 months before they show up in your dog’s blood. 

Book your puppy’s first heartworm test six months after your first visit, then again six months after that. From then on, your tests will need to be annually. If there are any lapses or breaks in treatment, your dog will need to be tested at six months intervals for the next two tests. 

Even with the preventative treatment, testing is 100% necessary as this will confirm that the prevention treatment is working effectively. As like many forms of treatment, heartworm treatment is not 100% positive. 

My Dog Has Heartworm, What Next? 


 Considering that heartworm is a fatal disease, many dog owners dread heartworm showing up in dog’s blood tests. Yet, there is every chance that your dog will make it, and it won’t leave any lasting implications. 

Your dog’s course of treatment may differ due to the severity of the infection and the health of your pet, but you can expect that a similar course of treatment to the one which we have outlined below. 

  1. Your vet may need to carry out additional tests to confirm the diagnosis and make sure that the treatment is absolutely necessary.
  2.  You’ll need to change your current exercise routine for your dog – especially if your dog gets a considerable amount of exercise each day. This is because physical exertion for your dog directly impacts the amount of damage which heartworm can cause in the heart. 
  3. Before treatment of the heartworm begins, your dog may need to be stabilized, in more serious instances of heartworm this process could take up to several months. 
  4. Once your dog is healthy enough for treatment, this process involves a series of injections administered by your vet over the duration of approximately 60 days. 
  5. Have a check up in 6 months’ time – the treatment will need to come from your vet.