Heartworm ranks as one of the most common, and most dangerous, parasitic infections in dogs and cats. While easily prevented, heartworms can be difficult and expensive to cure once your pet becomes infected.

Unfortunately, many pet owners misunderstand how dogs and cats get heartworm, leading to improper heartworm testing and prevention. Here are a few common myths about heartworm infestation in dogs and cats:

I don’t need to give my dog or cat heartworm prevention during cold months when there are no mosquitos. Many people believe that pets only need seasonal protection from heartworms and that it’s all right to skip heartworm prevention during colder months. However, it’s difficult to know for sure when “mosquito season” is truly over in your region, and mosquitos can also live successfully indoors through the winter. For these reasons, the American Heartworm Society recommends year-round preventive treatment for heartworms in dogs and cats, even in regions where winters are cold.

My dog (or cat) is an indoor pet, so he can’t get heartworms. Again, mosquitos can easily make it into your home, so even indoor dogs and cats need monthly heartworm protection year-round.

Animals with heartworm should be separated from other pets to prevent the spread of infection. Heartworm can only be spread through mosquito bites; your pet cannot get heartworm from another dog or cat. Even if a mosquito bites an infected animal and then bites your pet, there’s no need to worry – heartworm larvae need to undergo an incubation period within the mosquito before that mosquito can infect other animals. If your pet does have heartworm, however, you will need to keep him quiet and inactive for several months while he undergoes treatment, so separating him from any playmates for that reason may be a good idea!

People can contract heartworm from infected animals. Heartworms rarely infect humans, and the parasite only spreads through mosquito bites. So if your dog or cat has heartworms, there’s no need to worry – you will not contract heartworm infection from your pet.

I give my dog (or cat) monthly heartworm prevention, so I don’t need to get my pet tested for heartworms. Heartworm prevention is not foolproof, so annual heartworm tests should be an essential part of your pet’s heartworm protection plan. The longer heartworms live in your pet’s heart, the more damage they do. Early detection through an annual heartworm test can increase your pet’s chances for a full recovery.

Cats can’t get heartworms. While heartworm disease does occur more often in dogs, cats, ferrets, and other mammals can also contract the disease. So it’s important to protect your feline family members against heartworm, too!

Educating pet owners about the facts of heartworm and dispelling these common myths about heartworm infection in dogs and cats can help vets and veterinary staff ensure greater compliance with heartworm prevention recommendations – and overall healthier pets.

For more information about the symptoms, diagnosis, and treatment of heartworm infection in dogs, check out our Education page: What Is Canine Heartworm, and How Do I Know If My Dog Has Heartworm?