How long can worms last inside my cat?

I don't know that I could tell you how long one worm on its own would last. I'm sure there is a parasitologist that's shaking their head at me because I don't remember that anymore. But really, they continue to reproduce over time. You're probably not going to have one worm that dies off and never becomes an issue. You're going to have this worm that, generation after generation, is reproducing and continuing to cause problems, not only for your cat but also in the environment your cat is in. They're going to be spreading eggs and potential intestinal parasites to everybody around, including us and other pets.

They can last for quite some time, especially if they go undetected and they're not treated.

If we check a pet's stool sample, we're not looking for the worm. We're actually looking for the eggs of the worms. A cat or dog can have roundworms or hookworms, and I will mention whipworms because that can show up in dogs too, but it is very rare in cats. I personally, in a 40-year career, have never seen whipworms in a cat. Can it happen? Yes, but it would be extremely unusual. But if they get those worms, they live in the intestinal tract. They lay their eggs and keep the cycle going. However, it's easy to get rid of intestinal worms. We shouldn't have any problem getting rid of it. Just know that your cats can have it, and yes, they can keep them alive. It's virtually the same situation with a tapeworm since they get them from ingesting a flea. They get them from eating a small mammal, but they don't lay the eggs in the intestinal tract. Those little rice-like segments that I described pass out into the environment, and the eggs are in those segments. We're not going to find the eggs in the intestinal tract, which is why if your veterinarian does a fecal sample and checks for intestinal worms, they'll almost never see evidence of tapeworms simply because the eggs are not laid in the intestinal tract. That's what we're looking for. We generally rely on the owners to see the tapeworms pass in their own pets' poop. If we know that your pet has a flea problem or if they're a hunter, then yes, they will likely have tapeworms.

Worms can live for a long time inside a cat, depending on the species of the parasite. They can live for months, if not years, in the intestinal tract. It's important to have your cat's fecal material screened annually as an adult cat, and more frequently for kittens, to ensure they are not harboring parasites.