Caring cat owners are committed to doing whatever they can to keep their much loved feline friends in good health. This includes providing food and shelter as well as controlling parasites. Internal worms are very common in cats — one study of over 1500 owned cats showed that almost 20% were infested with roundworms1.
It’s therefore very important that if you share your life with a cat, you know how to keep roundworms and tapeworms under control, and this starts with understanding how cats become infected.
Roundworm and tapeworm differences
Adult roundworms are found in a cat’s small intestine. There are three ways in which a cat can pick up these worms. Firstly, they can become infected while nursing from their mum if she has roundworms while pregnant. Secondly, they may swallow infective eggs that have been passed into the soil in their environment. This usually happens when they groom themselves after having spending time outside. Lastly, cats that hunt could eat a rodent that’s carrying a burden of developing worms.
The most common tapeworm that infects cats is spread by fleas. The fleas eat the tapeworm eggs that stick to the fur around a cat’s tail then when the cat licks and cleans their fur, they swallow the infected fleas. The worm then continues its development inside their intestinal tract. Another species of tapeworm is passed to cats when they catch and eat infected rodents.
Signs and symptoms of worms in cats
It’s not possible to tell if your cat has roundworms just by looking at the faeces they leave in their litter box. Many cats show no obvious signs of worm infestation until their parasite burden makes them ill. You may then see lethargy, diarrhoea, and vomiting and they may have a pot-bellied appearance. Sometimes cats vomit up adult roundworms: they look very much like spaghetti. Young cats are particularly susceptible to the effects of roundworm and may even die if not cared for.
Tapeworms, on the other hand, can indeed be seen on a cat’s faeces and on the fur around the base of their tail. The worm segments look like moving grains of rice. Tapeworms tend not to cause ill health in cats, but the wriggling segments make their bottom itchy. This means that the only sign you may see is that they drag their bottom along the ground, or spend more time than normal licking that area.
It’s possible for your vet to examine a stool sample from your cat under the microscope to see if worm eggs are present, but this alone isn’t accurate enough to confirm an infestation. This is because worm eggs may not be shed at the time the sample is collected, or they may just not be present in the sample that’s looked at. It’s thought that many worm infestations in cats aren’t detected because there are no external signs of worms and no eggs detected in their faeces2.
Prevention and treatment of worms in cats
Because it’s not always possible to tell if your cat has intestinal worms, it’s best to deworm them regularly. This should be done more frequently when your cat is young: your veterinarian can recommend a suitable treatment schedule depending on which type of product you want to use. There are a number of product choices to treat intestinal worms in cats in tablet, paste, and liquid spot-on form so you’ll be able to find one that’s easy for you to use. Some cats can be difficult to give tablets to, if that’s the case with your puss then choose an alternative that’s easier to give them.
Environmental management is also a big part of preventing worms in cats. Because tapeworms are spread by fleas, control of these biting parasites will reduce the chance of infection in your cat3. Keeping rodents at bay will stop both roundworm and tapeworm infection. Also, if you promptly clean up cat faeces from your pet’s environment they are less likely to become infested with roundworm. This is because fresh faeces don’t spread roundworm; the worm larvae have to develop inside the egg before they can infect a cat. If you clean up after your cat regularly, larvae won’t have the opportunity to do this so the chance of reinfection with roundworm is reduced.
Intestinal worms aren’t just a risk to your pet’s health, they can make your family very ill. If a person swallows an infective roundworm egg, the larvae cannot complete their lifecycle because humans are not the right host for them. Instead of moving to our intestine, the larvae migrate through and damage our organs including our liver, heart and brain4. This is known as visceral larva migrans. If the larval worm makes its way to our eye, it is called ocular
larva migrans — which can cause blindness. These conditions are more common in children because they tend to be less consistent about washing their hands after they’ve cuddled their cat, too.
Prevention is always better than cure, and ill health in cats due to intestinal worms is easy to avoid. It’s a three step process: clean up faeces regularly, control fleas and rodents, and use a reliable worming treatment at regular intervals as directed by your vet.
1Beugnet, F., Bourdeau, P., Chalvet-Monfray, K., Cozma, V., Farkas, R., Guillot, J., Halos, L., Joachim, A., Losson, B., Miró, G., Otranto, D., Renaud, M. and Rinaldi, L. (2014). Parasites of domestic owned cats in Europe: co-infestations and risk factors. Parasites & Vectors, 7(1), p.291. 2Little, S., Adolph, C., Downie, K., Snider, T. and Reichard, M. (2015). High Prevalence of Covert Infection With Gastrointestinal Helminths in Cats. Journal of the American Animal Hospital Association, 51(6), pp.359-364. 3Fourie, J., Crafford, D., Horak, I. and Stanneck, D. (2012). Prophylactic treatment of flea-infested cats with an imidacloprid/flumethrin collar to forestall infection with Dipylidium caninum. Parasites & Vectors, 5(1), p.151. 4Ecevit, C., Bag, o., Vergin, C. and Ozturk, A. (2013). Visceral Larva Migrans Presenting with Hypereosinophilia. Turkish Journal of Parasitology, 37(1), pp.58-60.
Author info: Dr Audrey Harvey is a graduate of the University of Queensland, Australia, and has worked in small animal practices for 25 years. She is particularly interested in obesity management and the role of exercise in resolving behaviour problems in dogs.