Notes on Fleas

Fleas are very small insects. They are all flightless and do not have eyes, although two ocelli may be present. Their antennaes are short and their mouthparts are adapted for piercing and sucking. The female flea lays a few eggs daily that total up to 300 to 400 in its lifetime. The eggs are laid usually on animals and most drop off where they spend most of their time. Bedding, floor crevices, carpeting, along baseboards and areas near their favorite sleeping and napping sites are especially likely places where eggs will be found. These eggs hatch into larvae, which are baby fleas. The larvae spin a cocoon and, depending on environmental conditions, emerge as adults in as few as five days. The adult fleas then mate after a blood meal and then lay eggs. The life cycle is then repeated--until control measures break the cycle. The total life cycle can last from 25 days to several months. The bodies of both adults and young fleas have many backward pointing hairs and powerful leg muscles. Fleas can jump 80 times their own height and 150 times their body length. Fleas have many mites and parasites and can have up to 150 living in them at one time.
Adult fleas can cause medical problems including flea allergy dermatitis (FAD), tapeworms, secondary skin irritations and, in extreme cases, anemia. Some people may have a severe reaction, such as a general rash or inflammation, which can result in secondary infections caused by scratching the irritated skin area. Fleas may transmit bubonic plague from rodent to rodent and from rodent to humans. Tapeworms normally infest dogs and cats but can appear in children if parts of infested fleas are accidentally consumed. Fleas have been hated by humans for a long time. The role of pests and disease in human history is often neglected and the plague is considered to have caused more human grief and fear than any other single cause and to have changed the course of history more than any other force. Three main periods of