Written by a Zeus Services Certified Technician
We treat flea infestations across every London borough, with pet-safe formulations available and same-day appointments.
The 95% You Never See
Most people assume fleas are primarily a "pet problem" — treat the cat or dog, job done. In reality, adult fleas biting your pet make up only around 5% of the total infestation. The remaining 95% exists as eggs, larvae and pupae scattered through carpets, soft furnishings, pet bedding and gaps in floorboards. Flea pupae are particularly resilient — they can lie dormant for months, even up to 18 months, only hatching when they detect the vibration and warmth of a nearby host.
Why Fleas Show Up Even If You Have No Pets
This is one of the most common flea-related questions we get, especially in London rental properties. If a previous occupant had a cat or dog, flea pupae can remain dormant in the carpet and floorboards long after they moved out. When a new tenant moves in — bringing warmth, movement and vibration — dormant pupae hatch en masse, causing a sudden flea "infestation" in a property with no pets at all.
What Actually Breaks the Cycle
1. Treat the Pet and the Property on the Same Day
If your pet is treated with a vet-approved spot-on or spray but the property isn't treated simultaneously, the environment will simply reinfest your pet within days. Both need to happen together.
2. Vacuum Thoroughly Before Treatment, Not After
Vacuuming before a professional visit stimulates dormant pupae to hatch, making them vulnerable to the insecticide rather than surviving safely tucked away in carpet fibres.
3. Use a Residual Insecticide With an IGR
A professional residual spray kills adult fleas on contact, while an insect growth regulator (IGR) stops eggs and larvae developing into biting adults — breaking the lifecycle rather than just killing what's currently active.
4. Don't Re-Vacuum for at Least 2 Weeks
It's counterintuitive, but vacuuming too soon after treatment removes the residual insecticide from carpet fibres before it has finished working through the remaining life stages.
Some Activity After Treatment Is Normal
Because flea pupae continue hatching for up to two weeks after treatment, you may still notice occasional fleas for a short period afterwards. This isn't treatment failure — the residual insecticide kills each newly hatched flea as it emerges. Activity should steadily decline and stop within that window.