Why Do Indoor Cats Get Worms?

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Some owners are shocked to learn that their indoor kitty caught a case of worms, but this scenario isn't unusual. While outdoor cats are more likely to pick up internal parasites and other infectious agents, felines confined to the home can also ingest or inhale worm eggs around the home.


Indoor cats can still be exposed to worms.
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Once infected with worms, your cat may experience nausea, vomiting, and anemia, and some cases are even fatal. That's why it's so important to get your cat to the veterinarian for a proper diagnosis and treatment with a cat dewormer if you suspect she has worms.


Cats and intestinal worms

When it comes to parasites, your cat's predatory instinct works against him. Rodents, insects, and other household pests can harbor worm eggs, which are passed on to your kitty when he devours them. Unfortunately, many pests can enter your home through crawl spaces, cracks, and crevices and can scurry in through open windows, where they soon can become your cat's prey.


Mice and cockroaches are just some of the many critters that can carry roundworm eggs. When fleas bite rodents, they can become infected with tapeworm eggs. Infected fleas then carry tapeworm eggs that are passed to your cat if he ingests the flea while grooming himself.

Heartworms and indoor cats

Although heartworms are considered a major problem for dogs, they are increasingly affecting cats too. When a mosquito bites an animal infected with heartworms, the mosquito then carries the larvae. Once an infected mosquito flies into your home and feeds on your cat's blood, it can transmit heartworms to your pet by biting her.


Rodents, insects, and other household pests can harbor worm eggs,
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Once infected with heartworms, your cat can become extremely ill. Heartworms eventually travel to the heart and lungs through your cat's bloodstream. In some instances, heartworm infections can be fatal, and there is no approved treatment for heartworms in cats.


Worms in the environment

Even if your kitty never goes outside, there's a good chance that members of the household come and go on a daily basis. Outside animals infected with roundworms, hookworms, and tapeworms expel the eggs of these parasites in their feces, which then infect the soil. Microscopic worm eggs found in the soil can lay dormant for months, so it's easy to track them in on clothing and footwear.


There's no way to avoid worm eggs completely when you are outdoors, but you can lower the chances of contamination by removing or cleaning your shoes before entering the house. You'll also want to wash your clothing if you've spent time sitting on the ground outdoors.


Cat to cat worm transmission

If you have both indoor and outdoor kitties, be prepared for parasites and diseases to spread between them. Your cat can pick up a case of worms by sharing a litter box or food and water bowls with an infected cat.


Mother cats can spread intestinal worms to their kittens in the womb if they are infected. So, even if your kitten has never been outdoors, she could have gotten worms from her mother.

Worm medicine for cats

Take your cat to the veterinarian if you suspect that he might have worms. The doctor will do blood and fecal tests to determine whether your pet needs a cat dewormer. Worming medicine for cats is usually given orally, or your vet may give your cat a shot to kill off the parasites in his system.

Your vet may also recommend a heartworm preventative medication for your cat. These medications are usually given orally once a month and will also repel or kill other pests, like fleas and some intestinal worms.

Worms and people

Roundworms, tapeworms, and other parasites can spread to humans.
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Roundworms, tapeworms, and other parasites can spread to humans, so keep children away from litter boxes and wash their hands after contact with the cat. Always wash your hands after petting your cat as well, especially if you know he is dealing with a worm infestation.



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