Even Indoor Cats Get Heartworms

Hi everyone! As you know last week I had a scare with Sammy testing positive for heartworm. Now that I have read up on heartworm in cats, I want to spread the word so everyone knows the risks. My vet has always recommended preventative and has posters in the exam rooms about heartworms in both cats and dogs. I chose to take my chances being that my cats are inside and hubby keeps the screens repaired. I do recall having two mosquitoes in the house this past summer though because heartworm crossed my mind when I saw them.

(isn’t Sammy handsome? )

I don’t have a medical background so I am going to give some links to read up on it. I will let you know that they affect cats and dogs in different ways. When a dog gets heartworm it is a death sentence ( unless treated), but with cats it does not always lead to death, but it can. A dog is a natural host for them, but a cat is not so if a cat does get exposed the chances of any worms surviving to the adult stage is less. A cat with them would have 1- 3 on average, but dogs have many more than that.

The mosquito is the nasty critter that spreads them. This is why I assumed my cats were safe because they don’t go outside, but mosquitoes do get inside despite our efforts to keep them out and all it takes is one bite.

There is a very costly and dangerous medicine to kill heartworms in dogs, but this is not an option in cats. If a cat does end up with adult heartworms, the worms can live for 2- 3 years in them. They can cause a respiratory illness resembling asthma. Many cats have no symptoms, but die suddenly.

Here are some excellent resources to learn more about it:

American Heartworm Society ( they have a map showing areas of greatest risk)

VCA page on heartworms in cats

Live Science (article about the importance of diagnosis)

Nova Cat Clinic (great explanation of how this is a lung disease, not heart)

I am going to be using preventative for now on after this scare. And poor Sammy is still not out of the woods because the first test showed he was positive for being exposed, the antigen test was negative, but there needs to be pregnant female worms to make it positive. I plan to have him tested again in a few months because it takes 6 months for them to reach maturity. I know this is all very confusing so please read the links to get a better explanation.

I highly recommend anyone with a cat use heartworm prevention. I am not sure if this is a problem in other countries, but in the USA it definitely is. If your cat already has an illness or is older you may choose not to, you need to discuss the pros and cons with your vet.My niece worked at a vet clinic for 10 years and she said they had a few cases per year of cats with heartworms and usually one death per year. That may not sound like a lot, but no one wants their cat to be the statistic, or any cat for that matter.

Please pray for two of our blogging buddies that are not feeling well. Feel free to visit them and wish them well.

Buddy Budd  Fur Everywhere