How to Tell If You Have Fleas
Fleas are tiny (2–3mm), fast-moving, and live mostly hidden in carpets, rugs, and pet bedding. Most people do not realise they have fleas until the bites become frequent — by which point the infestation is usually well established.
The cat flea (Ctenocephalides felis) is responsible for the vast majority of flea infestations in UK homes, affecting cats, dogs, and their owners. Fleas thrive in warm, humid environments, and centrally heated homes provide ideal conditions year-round.
Flea Bites
Flea bites are small, red, and intensely itchy. They typically appear on the lower legs and ankles, as fleas jump from carpets and pet bedding onto the nearest host at ground level.
Bites often appear in clusters or irregular lines. They may develop a small red halo around the central bite point. Some people react more severely than others — and pet owners may assume bites are from mosquitoes until the pattern becomes clear.
Pet Scratching and Restlessness
Excessive scratching, biting at the skin, restlessness, and hair loss (particularly around the base of the tail, belly, and neck) are common signs of fleas on cats and dogs.
Some animals develop flea allergy dermatitis (FAD) — an allergic reaction to flea saliva — which causes intense itching from even a small number of bites. If your pet is scratching more than usual, check for fleas immediately.
Flea Dirt
Flea dirt (faeces) looks like tiny black specks — like fine ground pepper — in your pet's fur, on pet bedding, or on furniture where your pet rests.
To confirm it is flea dirt rather than ordinary debris, place some on a damp white tissue or kitchen roll. If it dissolves into reddish-brown streaks, it is digested blood — confirmation of fleas.
Seeing Fleas
You may see fleas moving quickly through your pet's fur, particularly in the areas where fur is thinner — around the ears, belly, and base of the tail. On light-coloured pets, they are easier to spot.
Fleas on carpets are harder to see. Try wearing white socks and walking slowly across the carpet — fleas may jump onto the socks and be visible against the white fabric.
Fleas in a Home Without Pets
Flea infestations can occur in homes with no current pets. This commonly happens in two situations.
The first is when moving into a property where previous occupants had pets. Flea pupae can remain dormant in carpets for months, hatching when they detect vibration and warmth from new occupants.
The second is after a holiday or extended absence. Dormant pupae hatch en masse when people return, leading to a sudden, intense wave of biting.
Where to Check for Fleas
Fleas spend most of their time off the host. Eggs fall from the pet into carpets, rugs, and cracks in hard floors, where larvae develop in dark, undisturbed areas.
- Pet bedding — the highest concentration of eggs, larvae, and flea dirt.
- Carpets and rugs — particularly under furniture and in areas where pets rest.
- Between sofa cushions — if pets sit on the sofa.
- Cracks between floorboards — flea larvae migrate towards dark gaps.
- Car seats and boot carpets — if your pet travels in the car.
- Skirting board edges — larvae develop in the dark space where carpet meets skirting.
When to Get a Professional Treatment
If you have been treating your pets and cleaning for more than two weeks with no improvement, if bites are frequent, or if you can see fleas jumping on carpets, professional treatment will resolve the problem much faster.
A professional flea treatment uses residual insecticides and growth regulators that keep working for weeks after application, breaking the lifecycle completely. At BuzzKill, treatments are fast and effective, with no call-out charge. Get in touch for a free assessment.
Need professional help? BuzzKill offers fast, reliable flea treatment services across London and Essex.