Human flea
The human flea, scientifically known as Pulex irritans, is a small parasitic insect that primarily feeds on the blood of humans but can also infest other mammals such as pigs, cats, dogs, goats, and rats. Measuring between 1.5 and 4 millimeters in length, the human flea possesses specialized mouthparts that allow it to pierce the skin of its host and extract blood, often resulting in itching and skin irritation. These fleas are characterized by their body structure, which includes overlapping plates and six pairs of legs, with the hind legs being particularly adapted for jumping.
Human fleas thrive in various environments, especially in areas with poor sanitation. They reproduce by laying between eight to twelve eggs in the skin of their host, and the lifecycle includes a larval stage where they feed on the host’s dead skin before spinning a cocoon and emerging as adults. The lifespan of a human flea can vary significantly, ranging from 18 days up to two years. Despite their reputation as pests, human fleas are not considered a threatened species. Interestingly, they have also been part of cultural phenomena, such as flea circuses, which entertained audiences with the illusion of trained flea performances.
On this Page
Subject Terms
Human flea
As its name suggests, the human flea is a parasite on humans. A parasite is an animal which lives on or in another animal. Although the human flea lives on human skin and feeds on human blood, it may also be found on pigs, cats, dogs, goats, and rats.
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Siphonaptera
Family: Pulicidae
Genus: Pulex
Species: Irritans
The human flea may grow to be beween 1 1/2 and four millimeters in length. This tiny creature's body is divided into many small, overlapping plates. At one end of its body is a tiny head with a pair of antennae and a set piercing mouthparts. On the plates of its thorax, or middle section, and abdomen, or tail section, the human flea has hundreds of thin hairs and spines. It also has six pairs of legs extending from its thorax. The human flea's hind legs are its largest legs and help the flea jump from place to place. This is especially helpful when the human flea jumps from one animal to another.
The human flea may be found on humans throughout the world, especially in places with poor sanitation. As a parasite, or animal which lives on or in another animal, the human flea lives on human skin and feeds on human blood. This flea may also be found biting pigs, cats, dogs, goats, and rats.
Like other parasites, the human flea feeds on its host. A host is an animal on or in which a parasite lives. The adult human flea feeds on the blood of its host. The specialized mouthparts of the human flea help it to suck blood. The human flea stabs its host with a hollow mouthpart while another part drives the hollow piece into the skin. The human flea rapidly repeats this motion to feed. Although the human, or another host, may feel no pain while the human flea is feeding, an itching, red, skin irritation usually appears when the flea is finished eating.
Mating for the human flea depends largely on its geographical location. In the tropics, this flea mates year-round, while in cooler climates it may only mate during the summer. After mating, the female lays between eight and 12 eggs in the skin of her host. A single female human flea may lay hundreds of eggs in her lifetime. After four to six days, larval human fleas hatch from their eggs. The larvae molt, or shed, their outer layers twice after they hatch. During this time the human flea feeds on the dead skin on the top layer of its host's body. It then spins a cocoon, or covering, around its body and continues growing. A larval flea may spend many months inside its cocoon before breaking free and emerging as an adult. During the cocoon stage of the human flea's life, it is known as a pupa. The average life span of the human flea is 18 days to one year. Some may live for up to two years.
Most hosts of human fleas use grooming habits to remove them. However, natural predators of human fleas include beetles, mites, and ants.
Although most people try to avoid fleas, some people have actually made money keeping fleas. Many years ago, country fairs displayed what were called flea circuses. A flea circus was a miniature circus that supposedly was being operated by trained fleas. A flea circus may have included tricycles, chariots, a tight rope, and a sword-fighting ring. Many people believed that the flea circus was just a joke and that it was actually mechanically operated. Other people said they could see the fleas. It is hard to know whether or not all flea circuses really had fleas, but some probably did, and the people who ran them claimed to use human fleas. They also claimed to feed those fleas on their own blood.
Human fleas are not a threatened species.
Bibliography
Tavella, Vincent J. “Can Fleas Live on Humans and Bite Us? Treatment and Prevention.” Healthline, 24 Sept. 2020, www.healthline.com/health/can-fleas-live-on-humans. Accessed 12 Apr. 2024.
Wyrwa, Jordan. “ADW: Pulex Irritans: Information.” Animal Diversity Web, 2011, animaldiversity.org/accounts/Pulex‗irritans. Accessed 12 Apr. 2024.