Fleas: spreaders of pestilence; makers of itch; ruiners of day; torturers of pets! Fleas are some of the most annoying insects out there. While wingless, fleas have six long and strong legs that enable them to jump and feed on their prey for growth and reproduction. Some of the most common fleas are dog and cat fleas. Both belong to the genus Ctenocephalides in the tribe of Archaepsyllini, and both are a nuisance. So is there really any difference between the two?
Dog Fleas vs. Cat Fleas
Cat fleas (Ctenocephalides felis) cause the most flea-related harm and notoriously spread pestilence—from rats to cats to humans. Cat fleas even feed on various livestock species and wild mammals, like golden jackals in Europe and Asia and brushtail possums in Australia.
Needless to say, cat fleas are the most common parasites living on cats and dogs the world over, with some strains appearing on ungulates such as deer and pigs.
While belonging to the same genus and having the same appearance as cat fleas, dog fleas (Ctenocephalides canis) are less common. Researchers have conducted fewer studies on them. Nonetheless, they are also considered important ectoparasites in that they can infest both domestic and wild animals.
Besides dogs, cats, and yes, humans, dog fleas have also been observed in several other mammals, including red foxes and rats. Rather unfortunately, they can act as intermediate hosts for certain parasitic worms.
To the naked eye, cat and dog fleas look the same. Cat fleas are about 1/8″ long and dark brown to black. Their shells look hard and shiny. Dog fleas measure similarly in size and have the same coloring. But under a microscope, you’ll see that cat fleas have a rounded shell, while dog fleas’ bodies are flatter.
How Cat and Dog Fleas Make Themselves Known
Fleas can leave bites and so much more, but is there a difference in how illnesses from cat and dog fleas present themselves?
Allergy Dermatitis (FAD)
Cats with fleas but no allergies may feel the flea itch or none at all. If they do have allergies, it could get so bad that the irritation can traumatize them. It also doesn’t matter how many fleas your pet has. The itch will be intense. If your cat is always licking herself, she probably has FAD.
FAD can manifest as a Christmas tree-shaped pattern of hair loss, and lesions are often found around the rump in dogs. You will also likely see flea bite marks or raised red dots on the canine’s skin. In cats, military dermatitis is more common, appearing as lumps and a stripe over their backline. In any case, cats and dogs are both susceptible to self-trauma, skin inflammation, and resulting infections because of FAD.
Fleas are intermediate hosts to parasites, including the tapeworm Dipylidium caninum. Because of this, animals that accidentally ingest fleas are likely to contract tapeworm diseases as well.
Tapeworm infection in dogs and cats is rarely serious, though you may see your dog dragging his bottom on the ground. This is the most common symptom of tapeworm infection in canines, but you will rarely see it in cats.
Dog Fleas and Cat Fleas—Is There Really a Difference?
Dog and cat fleas are not host-specific. Cat fleas can thrive in dogs and vice-versa. The truth is, about 95% of fleas affecting all animals in the U.S. are cat fleas. So yes, it’s easy to call them the same thing—to the naked eye, they are. But under a microscope, you’ll see that they are developing their own personal flea style.