Cat fleas are known as Ctenocephalides felis and typically prefer to feed from cats. However, they have been known to attack more animals especially outdoor, wild mammals like opossums, raccoons, or foxes. They can also live on humans and dogs if they happen to be closer at the point of hatching from cocoons from their pupae stage.
Physically, they have the typical flea form with a sideways flattened body, long and powerful legs and clear to brown body. On a microscopic level, these fleas have a more elongated head with a sharper curve than that of the dog flea. Their hind legs also happen to have 6 notches and not 8 like the dog variety.
In terms of distribution, cat fleas are most commonly found in North America. In fact most dogs in this part of the world that are affected by flea infestations carry this species and not the dog flea options. They are, however, also found in other continents including Europe although not in as many numbers as the dog fleas.
Cat fleas are also different from dog fleas in that they are notorious for spreading diseases. While the dog flea pretty much only carries flea tapeworms, cat fleas carry a variety of parasites and bacteria. These include Murine typhus, Rickettsia felis, Dipetalonema reconditum, Acanthocheilonemal reconditum, and the bacteria responsible for Lyme disease.
They also stand out in that they are rarely transferred so you can pet a cat with fleas. This is because although they can live on cat for 1 to 3 months, they die within days to two weeks of being off the host.