Ctenocephalides felis (Bouche), can elicit more than the proverbial itch. This species of blood feeder is one of the primary infestants encountered by homeowners.
Fleas are both medically and veterinarily significant because of their ability to transmit diseases like murine typhus and plague.
Although there are over 250 species of fleas described in North America (Pratt 1957), only a few are commonly encountered by humans with enough frequency to be considered pests.
Outdoors, fleas are most abundant during humid, rainy summers and are more common outside in the southern United States than in the north. Indoors, warmth and high relative humidities are conducive to large populations. The sudden appearance of large numbers of adult fleas in mid-summer and fall (”flea seasons”) is due in large part to the onset of higher humidities and temperatures which permit larval development to accelerate. Larvae may undergo arrested development in less than favorable conditions.
Adult fleas are small, brownish insects flattened from side to side, without wings but with powerful jumping legs.
Adults feed on blood, and females deposit eggs only after a blood meal. Most species remain on the host only long enough to feed. Nearly all species have host preferences but are not restricted to any one host species. This trait is responsible for the transmission of several diseases (e.g. plague or murine typhus) from one host species to another.
Adults can live for several years and go without feeding for months at a time under extreme conditions. Fleas can remain in a structure long after the host mammals have been removed. Depending on the species and environmental conditions, adults can breed from two weeks to two years after emerging.Adults prefer warm humid places and will leave a host if it dies.