Intestinal worms are classified into two main groups: cestodes, or flatworms, and nematodes, which are round.
Flatworms
*Dipylidium caninum* is the most common cestode in dogs and cats. Infection occurs when the animal ingests a flea (through licking or nibbling its fur) carrying the parasite in its larval stage. The larva then develops in the small intestine of the definitive host, growing into a flatworm that can reach several tens of centimeters in length. It consists of a head-like structure called a scolex, equipped with four suckers and a retractable rostellum armed with hooks, as well as a chain of segments containing eggs. These segments detach one by one and are expelled through the anus. They are usually easily recognizable around the anal area, resembling cucumber seeds or grains of rice if dried. While relatively harmless, they cause discomfort for infested pets, leading to anal itching. Your dog or cat may then bite at its hindquarters or "scoot" across the floor.
*Taenia taeniformis* is the second most common flatworm in cats, after *Dipylidium caninum*. It primarily affects hunting animals since its intermediate host is the mouse. As an adult, this worm can reach up to 60 cm in length. *Taenia saginata*, often mistakenly called the "solitary worm," can grow up to 15 meters long! It is strictly specific to humans and cannot infest our four-legged companions.
Roundworms
Toxocara includes several species. T. canis, also known as "canine roundworm," is the most common parasite in dogs worldwide. This white worm resides in the anterior part of the small intestine and measures 9 to 17 cm. It often coils into clusters, resembling spaghetti! Puppies are frequently infected. When it affects humans, T. canismigrates to other organs. T. leonina is slightly smaller, infects both cats and dogs, and does not migrate outside the digestive tract. T. catiprimarily infests cats and measures only 5 to 10 cm.
How to Protect My Pet?
A dewormer is a medication that fights intestinal parasites and worms. This medication has no residual effect, meaning it is only active at the time it is taken. Regular and systematic deworming, even in the absence of parasitic symptoms, helps protect dogs and cats from a very young age and prevents human contamination. Talk to your vet about it.
Learn more:
ESCCAP (European Scientific Counsel Companion Animal Parasites) is an independent, non-profit organization that develops and disseminates guidelines for the treatment and prevention of major internal and external parasitic infections in pets, including intestinal worms and advice on deworming.
