Fleas feed on blood and they want blood from mammals. This includes pets, sure, and other animals, but they are more than willing to feed on humans, too. Fleas will bite a human to get at the blood vessels below the skin and their bodies are built to do so.

Why do fleas bite me and no one else?

Cat, dog, and rat fleas do not live on people, but they will bite a human if they encounter one and are looking for a blood meal. Fleas most often bite people around the legs and the ankles. The resulting red bump is an allergic reaction to flea saliva.

How do I stop fleas from biting me?