Cat Health Issues: 3 Alarming Facts You Didn’t Know About Heartworm in Cats

Heartworms in CatsMany pet owners know too little about heartworm in cats until it’s too late. Signs of heartworm can either be barely detectable or very intense, and often the first time the disease rears its ugly head is in the form of a cat’s sudden collapse, or even death. While this used to be one of the rarer cat medical issues, there have been more cases appearing in certain areas lately, so pet lovers need to become educated on how to protect their kitties from this serious cat health issue.

How much do you know about heartworm in cats, and what are you doing for your cat to prevent this serious Ragdoll cat health issue? Below are three pieces of critical information about heartworm disease in cats to consider:

#1 Heartworm is extremely difficult to diagnose

Often cats don’t show signs of heartworm right away, and diagnosis is further complicated by the fact that it’s not possible for vets to test specifically for heartworm in cats. Instead, vets rely on a combination of x-rays, urine analysis, an ECG, and/or antigen and antibody tests to determine whether heartworm is the cause of a cat’s health problems.

Heartworms are transmitted by mosquitos, which inject baby heartworms called larvae. The larvae grow once inside the animal’s body and can cause different diseases depending on that animal’s response to the worm as it matures. It is believed that the baby worms cause the lion’s share of the disease.
The lungs of the cat are exquisitely sensitive to the presence of larvae, and because of this the lungs can set up an intense immune response around the little lower airways that acts like asthma. Even if these immature worms never fully develop, they can cause heartworm associated respiratory disease (HARD), another long-term cat health problem. Much less frequent, but more immediately life threatening, is the disease caused by the adult worm. Adult worms live in the heart and cause lots of irritation in the major vessels near the heart, a condition that could be chronic or life-threatening.

Though heartworm symptoms vary in kind and degree by cat, some general cat health symptoms that could be indicators of heartworm include coughing, vomiting, difficulty breathing, weight loss, appetite loss, and even irregular heartbeats or a heart murmur, which could be detected by your vet. If your cat starts exhibiting these symptoms, get them to a vet as soon as possible and ask them what further tests they can do to check for heartworm.

#2 Heartworm is different in cats than in dogs

It may surprise a lot of pet owners to know that heartworm manifests itself differently in cats than in dogs. Though an increase of heartworm in dogs in an area can put cats at greater risk, cats are unusual hosts for heartworms. The good news is that the disease is less common in cats than in dogs, and the problem often naturally cures itself before the heartworms reach an adult stage. That being said, heartworm diagnosis numbers have been on the rise in some areas, and even immature heartworms who never get to the point of damaging the heart can still cause issues in cats’ lungs, so it is essential to be vigilant.

Unfortunately, another way that dogs and cats differ is that the medication used to treat heartworm in dogs cannot be used on cats, so at present there is no cure for a full-blown case of cat heartworm, just options for managing the condition and preventative measures.

#3 Prevention is your best weapon

Since heartworm is so difficult to diagnose and treat in time, this leaves prevention as the best way to protect your kitty. Fortunately, there are many preventative measures that can be taken to avoid heartworm disease in cats. Several monthly preventative medications are available. Novartis’ Interceptor Flavor Tabs (milbemycin oxime) are probably the best, as they contain no chemicals and are administered through an oral flavored pill. There are topical applications as well. Advantage Multi is a good flea product that is effective against heartworms and several other parasites. Revolution is another. It may not be quite as good on adult fleas, but it is good on heartworms. Another is an oral product called Heartguard™. If it is likely that your cat will be exposed to mosquitoes, then you might consider using one of these products.

Though heartworm is a serious threat to a cat’s health, if your cat is diagnosed with heartworm and it is caught in time, there are ways to manage the disease with good veterinary care and possibly even surgery to remove the worms. There is also the chance that the disease will self-terminate because of the short lifespan of the worms in cats. If you reach this stage, talk to your vet about a long-term plan, return regularly for x-rays and additional care, and continue to give your cat preventative treatments as directed.

The occurrence of heartworm disease in cats in the United States has been steadily increasing over the last several years in some areas. Although the hope is that as vets learn more about the disease, more options for treating or controlling it will become available, it’s crucial for cat owners to stay educated about prevention options for this life-threatening cat health issue.

What preventative measures do you take to protect your cat from heartworm?

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Hi, I’m Jenny Dean, creator of Floppycats! Ever since my Aunt got the first Ragdoll cat in our family, I have loved the breed. Inspired by my childhood Ragdoll cat, Rags, I created Floppycats to connect, share and inspire other Ragdoll cat lovers around the world,

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  1. Does anybody know if European mosquitoes also spread heartworms? I know there are some mosquitoes in my country (Finland) that spread diseases that could infect humans, but I’ve never heard of them affecting animals.

  2. Teresa Reid says:

    This is a devastating disease and one I hope and pray no one ever has to go through with their beloved kitties.Those worms are disgusting! My cats are strictly inside as Patti stated that Miss Pink Sugarbelle is. I am on the fence about whether to give them the heartworm medication because of their very limited exposure to mosquitoes and hopefully negating them ever contracting the disease (God forbid).

    Having had about 5 of my 20 cats I’ve had in my lifetime that succumbed to the dreaded renal disease and thyroid disease, I am very cautious about putting anything in their system or on their skin that they could lick off to kill insects, etc. Those 5 cats that did succumb to renal failure all had topical flea/tick control.

    So, I’m not sold on these preventatives that they wouldn’t cause a worse or fatal condition in the years to follow. Will just stick with closely monitoring them cause even when they get a hiccup, I’m on it right away.♥♥♥

  3. Great post, Jenny! Thank you so very much for this very important and informative info.

    At this time, we do not use any preventative treatment for heartworm for Miss PSB since her exposure to the risk is very low (she’s an indoor kitty and we live on the second floor of our apartment building so our exposure for mosquitoes is very low even when we get rainy weather as our front door is far removed from any areas where puddles might exist as a breeding ground for those pesky skeeters in the rainy season). I don’t think I’ve ever seen a mosquito in our apartment for the many years we’ve lived here (and I’m a natural mosquito magnet!).

    Big hugs!

    Patti & Miss Pink Sugarbelle 🙂 <3

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