Fleas: Siphonaptera

The bites of the dog, cat, and human fleas are very annoying and may cause itching and allergic reactions in sensitive people. Scratching flea bites often causes further discomfort and leads to infections. Some fleas carry diseases that infect both humans and pets. Plague and other diseases are spread either through the bites of infected fleas or by rubbing the waste of infected fleas into the bite wounds. Eating fleas infected with parasitic worms and blood protozoan parasites can spread these harmful organisms to humans, dogs, rabbits, rats, and other animals.