Fleas are small, wingless insects (order Siphonaptera) that are external parasites, feeding on the blood of mammals and birds. Here are some key facts about fleas:

Characteristics:

Size: 1–4 mm long.
Color: Dark brown or reddish-brown.
Body: Laterally flattened (helps them move through fur/feathers).
Legs: Powerful hind legs for jumping (can leap up to 200 times their body length).
Mouthparts: Adapted for piercing skin and sucking blood.

Life Cycle:
Fleas undergo complete metamorphosis (egg → larva → pupa → adult):

Eggs – Laid on the host or in the environment (e.g., carpets, bedding).
Larvae – Worm-like, avoid light, feed on organic debris and flea feces ("flea dirt").
Pupae – Enclosed in a cocoon; can remain dormant for months until triggered by heat/vibrations.
Adults – Emerge to seek a blood meal within seconds to days.

Common Flea Species:

Cat flea (Ctenocephalides felis) – Most common, infests cats, dogs, and sometimes humans.
Dog flea (Ctenocephalides canis) – Less common than cat flea.
Human flea (Pulex irritans) – Rare in modern households.
Oriental rat flea (Xenopsylla cheopis) – Known for spreading plague.

Health Risks:

Itching & Allergies – Flea bites cause redness, swelling, and dermatitis (some pets develop flea allergy dermatitis).
Disease Transmission – Can carry pathogens like:
Plague (Yersinia pestis) (via rat fleas).
Murine typhus (Rickettsia typhi).
Tapeworms (Dipylidium caninum) (if ingested by pets).

Prevention & Control:

Pet Treatment – Use vet-approved flea collars, spot-on treatments, or oral medications.
Home Cleaning – Vacuum frequently, wash pet bedding, and use flea sprays/foggers.
Yard Maintenance – Keep grass short and treat outdoor areas if needed.
Regular Checks – Comb pets with a flea comb and look for "flea dirt" (black specks that turn red when wet).

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