Fleas found on pets (cats, dogs, rabbits, and other species) are cat fleas. A heavy flea burden can be lethal to smaller or younger animals or for elderly pets allowed to go outside. These older animals do not groom well and are often debilitated by other diseases. The last thing a geriatric pet needs to worry about is a lethal flea infestation and it is especially important that these animals be well protected. On some level, it is obvious that fleas are blood-sucking insects but most people never put it together in their mind that enough fleas can cause a slow, life-threatening loss of blood. The cat flea is not at all selective about its host and has been known to kill calves through heavy infestation. Other conditions brought about via flea infestation include: Flea Allergic Dermatitis, Flea Anemia or Feline Infectious Anemia (a life-threatening blood parasite carried by fleas), Cat Scratch Fever (does not make the cat sick but the infected cat can make a person sick) and Common Tapeworm infection (not harmful but cosmetically unappealing).