Adult fleas are blood sucking ectoparasites which can cause pruritis, annoyance and anaemia if present in large numbers. [[Skin Immunologic - Pathology#Flea bite hypersensitivity|Flea allergic dermatitis]] can also occur where the animal becomes allergic to the antigens in the flea saliva triggering a hypersensitivity reaction when the flea bites. | Adult fleas are blood sucking ectoparasites which can cause pruritis, annoyance and anaemia if present in large numbers. [[Skin Immunologic - Pathology#Flea bite hypersensitivity|Flea allergic dermatitis]] can also occur where the animal becomes allergic to the antigens in the flea saliva triggering a hypersensitivity reaction when the flea bites. |