Why have fleas infested the house? - briefly
Fleas proliferate when a suitable host—typically pets or rodents—and a warm, humid environment combine with inadequate cleaning or untreated bedding. Their presence indicates that these conditions have persisted long enough for the insects to complete their life cycle inside the dwelling.
Why have fleas infested the house? - in detail
Fleas appear in a residence when conditions allow their life cycle to complete and adult insects can locate a blood source. Several factors commonly create such conditions.
- Pets – Dogs, cats, or other animals that spend time outdoors often bring adult fleas or eggs into the home. Even well‑treated animals can harbor immature stages that dislodge during grooming or sleeping.
- Wildlife intrusion – Rodents, squirrels, birds, or stray cats that enter through gaps in the foundation, attic, or chimney can carry fleas. Their nests provide a protected environment for eggs and larvae.
- Environmental humidity – Relative humidity between 70 % and 85 % supports egg hatching and larval development. Damp carpets, upholstery, or basements retain moisture, accelerating population growth.
- Temperature range – Ambient temperatures of 20 °C to 30 °C speed the flea life cycle. Central heating or insufficient ventilation can maintain this range year‑round.
- Organic debris – Flea larvae feed on adult flea feces (blood‑stained specks), dead skin, and other organic matter. Accumulated lint, pet hair, and dust in carpets or cracks provide a food source.
- Structural gaps – Cracks in flooring, baseboards, or wall voids allow adult fleas to drop from outdoor hosts onto interior surfaces, where they can lay eggs.
- Human transport – Clothing, shoes, or luggage that have contacted infested areas can introduce fleas inadvertently.
The flea life cycle consists of egg, larva, pupa, and adult stages. Eggs are deposited on the host but fall into the surrounding environment. Under favorable humidity and temperature, larvae develop within 5–10 days, spin cocoons, and emerge as adults ready to seek a blood meal. A single female can produce several hundred eggs, so once the cycle establishes, numbers increase rapidly.
Understanding these contributors enables targeted control measures: regular veterinary treatment for pets, sealing entry points, reducing indoor humidity, thorough vacuuming of carpets and upholstery, and applying appropriate insecticides to cracks and crevices. Prompt intervention interrupts the life cycle and prevents a self‑sustaining infestation.