Tapeworms are the most common parasite to be observed by my clients, as they are one of the few that are visible to the naked eye. Tapeworm segments can often be seen in fresh feces or hanging from an infected dog or cat’s anus.
Like many other parasites, tapeworms have primary and secondary hosts. The species that we are primarily concerned with in small animal practice use dogs and cats as their primary hosts and fleas as their secondary hosts. Tapeworm eggs are excreted from your pet in their stool, where the eggs are then ingested by flea larvae. The fleas pupate, become adult fleas, and then begin feeding on a dog or cat. The fleas cause skin irritation when they feed, causing your pet to chew at their skin… ingesting the flea and allowing the tapeworm to mature and continue the cycle inside your pet’s bowels.
There are a couple of other tapeworm species that infect dogs and cats, though we do not normally see them here in the suburbs. A species that infects cats uses rats as their secondary host, and then infect the cat as the primary host when the rat is eaten by the cat. There is a species that infects dogs which uses rabbits as their secondary host.
Tapeworms do not typically cause any serious problems in dogs or cats, though they are distressing to owners because they are highly visible. The treatment for tapeworms is fairly straightforward and easy to administer. As an animal hospital, though, we are far more concerned with the source of the tapeworm infestation: fleas. Once your pet has an observable flea problem, it will take a significant period of time to completely eliminate them from your home, as you can read in our post on fleas. Fleas cause your pet a lot of irritation, and even a very small number of fleas can cause a skin allergy that can linger for a significant period of time.