Abstract: A method to protect a host animal from flea infestation by treating that animal with a composition that includes a compound that reduces protease activity of fleas feeding from the treated animal, thereby reducing flea burden on the animal and in the environment of the animal. The present invention also relates to compositions including flea protease vaccines, anti-flea protease antibodies and/or protease inhibitors. Also included in the present invention are soluble flea midgut preparations, flea protease proteins, nucleic acid molecules encoding such proteins and antibodies that selectively bind to such proteins. The present invention also includes methods to obtain and use such preparations, proteins, nucleic acid molecules, antibodies and protease inhibitors to protect an animal from flea infestation.

Abstract: A vaccine for protecting avian and mammalian subjects against flea infestation comprises the supernatant fraction of flea midgut, or the antigenic components thereof. This also has the effect of reducing flea populations in the environment of the subject. Antibodies raised by these vaccines are also useful in purification and diagnosis.