Tungidae- Sticktight and Chigoe fleas(Chiggers)
Pulicidae- Common fleas
Coptopsyllidae
Vermipsyllidae- Carnivore fleas
Rhopalopsyllidae- Marsupial fleas
Hypsophthalmidae
Stephanocircidae
Pygiopsyllidae
Hystrichopsyllidae- Rat and mouse fleas
Leptopsyllidae- Bird and rabbit fleas
Ischnopsyllidae- Bat fleas
Ceratophyllidae
Amphipsyllidae
Malacopsyllidae
Dolichopsyllidae- Rodent fleas
Ctenopsyllidae
Flea is the
common name for any of the small wingless insects of the order Siphonaptera.
Fleas are external parasites, living by hematophagy off the blood of mammals and
birds.
Note: There is also a genus of
Protozoa
named Siphonaptera
Some well known flea species include:
Cat Flea (Ctenocephalides felis),
Dog Flea (Ctenocephalides canis),
Human Flea (Pulex irritans),
Northern Rat Flea (Nosopsyllus fasciatus),
Oriental Rat Flea (Xenopsylla cheopis).
Flea bites on the back of a human
In most cases fleas are just a nuisance to their hosts, but some people and
some animals suffer
allergic reactions to flea saliva resulting in rashes.
Flea bites generally result in the formation of a slightly-raised swollen
itching spot with a single puncture point at the center.
However, fleas can act as a
vector for disease. One devastating example of this was the bubonic plague,
transmitted between rodents and humans. Murine typhus (endemic typhus) fever,
and in some cases tapeworms, Hymenolepiscan also be transmitted by fleas.
Life Cycle
Hooke's drawing of a flea in Micrographia
Fleas pass through a complete life cycle consisting of egg, larva, pupa and
adult. Completion of the life cycle from egg to adult varies from two weeks
to eight months depending on the temperature, humidity, food, and species. Normally
after a blood meal, the female flea lays about 15 to 20 eggs per day – up to
600 in its lifetime – usually on the host (dogs, cats,
rats, rabbits, mice, squirrels, chipmunks, raccoons, opossums, foxes, chickens,
humans, etc.). Eggs loosely laid in the hair coat drop out almost anywhere,
especially where the host rests, sleeps or nests (rugs, carpets, upholstered
furniture, cat or dog boxes, kennels, sand boxes, etc.).
Eggs hatch between two days to two weeks into
larvae found
indoors in and along floor cracks, crevices, along baseboards, under rug edges
and in furniture or beds. Outdoor development occurs in sandy gravel soils
(moist sand boxes, dirt crawlspace under the house, under shrubs, etc.) where
the host may rest or sleep. Sand and gravel are very suitable for larval
development which is the reason fleas are erroneously called "sand fleas."
Larvae are blind, avoid light, pass through three larval
instars and take a week to several months to develop. Their food consists of
digested blood from adult flea feces, dead skin, hair, feathers, and other
organic debris; larvae do not suck blood. Pupae mature to adulthood within a
silken cocoon woven by
the larva to which pet hair, carpet fiber, dust, grass cuttings, and other
debris adheres. In about five to fourteen days, adult fleas emerge or may remain
resting in the cocoon until the detection of vibration (pet and people
movement), pressure (host animal lying down on them), heat, noise, or carbon
dioxide (meaning a potential blood source is near). Most fleas overwinter in the
larval or pupal stage with survival and growth best during warm, moist winters
and spring.
Flea bites can be treated with Calamine Lotion or 0.5-1% conc. hydrocortisone
cream. Lufenuron is a veterinary medicine that attacks the larval flea's ability
to produce chitin.
Flea bites on the back of a human
Hooke's drawing of a flea in Micrographia