Fleas are one of the more important groups of insect pests because they not only cause discomfort by biting, but they can transmit several diseases such as plague and murine typhus. Cat and dog fleas are the most common domestic flea. They are found throughout the world.
Adults are about 1/8” long. Color is brownish black to black, but reddish black when full of blood. Females lay 4-8 eggs after each blood meal, laying some 400-500 during their lifetime. The eggs are smooth and not glued/stick to the hairs or body but are deposited on or between hairs, or in the nest or bedding material. Hence eggs deposited on the animal either fall or are shaken off, and are frequently found in cracks and crevices where pets sleep or frequent. Fleas are typically found where animals sleep or frequent, including along their usual avenue of travel, because this is where eggs and adult fecal blood accumulate. Most larvae will be found in similar places but especially in areas with high moisture which is necessary to their survival.
It is not necessary to have pets in the building in order to have fleas present. Since fleas can jump 6” vertically, they can easily hitch a ride on shoes, trousers, etc. Many vacationers who may have been unaware of the few adult fleas present, are often greeted and severely attacked upon their return. This can occur even if the building has been vacant of animals and people for as long as 6 months or so. This situation can occur because of the potentially long pupal period, adults can live for months without food, and because fleas have not been removed via normal vacuuming.