Fleas are excessively troublesome insect pests that are carried by mammals (human and animal) and birds. They can quickly infest homes, bird cages and poultry houses if untreated. Both the male flea and female flea bite and suck blood from their carrier or host. The bite will often leave an itchy, red spot at and around the point of contact. Some fleas transmit diseases such as bubonic plague, endemic typhus and tularemia to humans, hence it is important to identify and exterminate them as soon as they have been identified.
Several kinds of fleas attack mammals and birds. The dog flea and the cat flea, which look very much alike, are the most widespread and the most troublesome as household pests. Both species attack dogs and cats, and sometimes humans, especially if the family pet(s) are temporarily away and the flea has no substitute to feed on.