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Do Cats Need Heartworm Prevention?

Dog parents know that heartworms are a serious threat, but do we also need to worry about our feline friends?  

While feline infections are less prevalent, cats can and do contract heartworms — and the consequences can be devastating. Get the facts on heartworm disease in cats to assess your pet’s risk and choose the right options for preventative care. 

cat stretching heartworm preventionHow Common Are Heartworms in Cats?

Compared to dogs, cats are about 5-20% as likely to contract the parasite — a fact that makes some pet parents complacent about prevention. Cats’ body chemistry and physiology make them less-than-ideal hosts for heartworms, but they are certainly still susceptible to infection. 

Even though heartworms are less likely to survive to maturity in a healthy cat’s body, worms at the larval stage can still cause deadly inflammation in the organ systems. Because of their relatively small body size, a worm load that would be considered quite low for a dog can be overwhelming for a cat. 

Which Cats Are at the Greatest Risk for Heartworms?

When a mosquito bites an animal with mature heartworms, it becomes a temporary host for the parasite’s pre-larvae. When that same mosquito moves on to feed on healthy animals, it can transmit this microscopic pre-larvae through the bite wound. 

For this reason, heartworm infections are most prevalent in areas with heavy mosquito populations. The Southeastern US reports the most heartworm cases, with infections rising in the summer. 

Naturally, cats that spend time outside are vulnerable to mosquito bites, but even indoor-only cats are susceptible to tiny pests that find their way inside the home. In fact, 1 in 4 cats diagnosed with heartworms were reported to be indoor-only

Symptoms of Heartworms in Catsheartworm prevention orange cat

Symptoms of heartworms in cats can vary tremendously. Some cats clear the infection on their own, while others experience severe respiratory distress. Unfortunately, some cats are asymptomatic but die suddenly due to acute complications. 

Even though worms may not be able to thrive in cats’ bodies, inflammation in the lungs caused when the heartworms die can lead to HARD (heartworm associated respiratory disease). The associated symptoms are fairly non-specific and can be mistaken for a number of other conditions like the flu or feline asthma. Be on the lookout for:

  • Coughing
  • Wheezing
  • Increased respiratory rate
  • Trouble breathing
  • Vomiting
  • Gagging
  • Loss of appetite
  • Lethargy

How to Treat Heartworms in Cats

There are currently no FDA-approved heartworm drugs for cats. Medications that are effective for dogs aren’t safe for cats. 

While there is no way to address the heartworm infection directly, your vet may be able to manage symptoms with steroids, antibiotics, and bronchodilators. Unfortunately, surgical options are typically considered too risky. 

Prevention is the Best Treatment

While feline heartworms aren’t treatable, they are preventable

The best way to reduce your cat’s risk of facing this tricky prognosis is year-round preventative care. Heartworm prevention is available through monthly chewables, topical drops, or bi-annual injectables. 

Talk to your vet to choose the best solution for you and your cat.