Fleas can cause problems for pets ranging from minor to life-threatening. Not only can these parasites cause severe itching, irritation, and allergies, but they can also transmit tapeworms and diseases. Fleas can infest dogs, cats, ferrets, mice, and rats. And fleas don’t just stay on pets; they can bite people, too. For more information, contact us or see the flea article in the Pet Health Library on our site.