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Fleas In The Carpet
Itchy bites round the ankles, black specks in the pet's bedding, and fleas jumping when you walk across the room.
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What's happening?
The fleas you see are a small fraction of the problem. Most of a cat or dog flea population exists as eggs, larvae and pupae in carpet pile, floorboard gaps, pet bedding and upholstery, and the pupae are the difficulty: they are sealed, resistant to insecticide, and can lie dormant for months until warmth, carbon dioxide and vibration tell them a host has arrived. That is why an empty house can produce a sudden wave of fleas the day people return from holiday, and why one treatment is never enough. It also explains the most common failure: treating the pet but not the house, which leaves the entire reservoir intact and the reinfestation guaranteed.
What usually causes it?
- An untreated or lapsed-treatment cat or dog bringing fleas in and seeding the carpet
- A dormant pupae reservoir hatching when a house warms up or is reoccupied after being empty
- Wildlife under a floor or in a loft — hedgehogs, foxes, squirrels, birds — leaving fleas behind
- Moving into a property where the previous occupants had pets
- Pet bedding, sofas and beds acting as the main breeding site rather than the floor
- Treating the pet but not the house, or the house but not the pet
- Stopping vacuuming during treatment, which is what triggers the pupae to hatch into it
Is it dangerous?
Not seriously. Flea bites itch, cluster around ankles and lower legs, and can become infected if scratched; some people and animals react strongly. Fleas can transmit tapeworm to pets. The genuine hazard is product misuse: never use a dog product on a cat, and in particular never use a permethrin-based dog spot-on on a cat — it is highly toxic to cats and a common cause of poisoning. Get flea products for pets from a vet rather than guessing.
Can I fix it myself?
Partly, and one step matters more than the rest. Treat every pet in the household at the same time with a product from your vet. Wash all pet bedding at 60°C. Then vacuum thoroughly and daily — floors, carpet edges, under furniture, upholstery — because the vibration is what makes dormant pupae hatch when insecticide is present to kill them. Empty the vacuum outside into a sealed bag. Do not stop vacuuming after treatment, and do not use a household insecticide near fish tanks or on pets.
When should you call a pest controller?
Call a pest controller when bites continue after two or three weeks of treating the pets and vacuuming daily, when the infestation covers several rooms, or when there is no pet in the house — which usually means wildlife under the floor or in the loft, and that source has to be found. Professional treatment combines a residual insecticide with an insect growth regulator that breaks the life cycle, which is the part amateur products generally lack.
What will the pest controller actually do?
- Confirm fleas rather than another biting insect, and identify the likely host
- Inspect for a wildlife source under floors, in lofts or in a chimney where there is no pet
- Apply a residual insecticide with an insect growth regulator to floors, edges and harbourage
- Treat upholstery, pet bedding areas and floor voids where the larvae actually live
- Set out the vacuuming and preparation schedule that decides whether the treatment holds
- Return to check, since dormant pupae can continue hatching for weeks
Frequently asked questions
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