Q. Our vet said that our dog has cat fleas. We don’t even have a cat and we haven’t had any cats visiting, or any cats in our yard that I know of. How can the dog have cat fleas?

A. It’s a misconception that dogs have dog fleas and cats have cat fleas. In the U.S., you can pretty well assume that all dogs that have fleas have cat fleas, Ctenocephalides felis. Cat fleas are, by far, the most common flea on pets, both dogs and cats. About 95% of all pet flea infestations in the U.S. are cat fleas. Dog fleas can also occur on dogs and cats (and rabbits), but are much less common in the U.S.; they are more common in Europe.

Cat fleas prefer to live on dogs and cats, but will also live on some wild animals that may frequent your yard, like opossums, raccoons, or foxes. There’s no way to know where your dog’s fleas came from in the first place, but it’s very possible that he picked them up in your yard. As flea eggs are laid and drop off of the wild animal, the larvae hatch, develop, and pupate in your yard, or in the animal’s nest. About two days after the adult flea emerges from the pupal cocoon, it will have found a host animal and taken its first blood meal.

Pet owners treat their pets for fleas and may treat their home for fleas, but they don’t think to treat their yard. They think they’ve finally solved their flea problem, but soon Rover has fleas again and they can’t figure out why. Probably the most common way that pets get reinfested with fleas is when they pick them up outside. Your dog could be picking up fleas left by wild animals, or by neighborhood pets, or even fleas from his own previous infestation which have since completed development. If you think you might have a flea population in your yard, give Colonial a call. We can treat your home for cat fleas and we can treat your yard for cat fleas as well.