Experts say that the new breed of well-endowed beasts will come out of hibernation this autumn and could turn up in millions of homes, carried in by pets.
The so-called super-fleas are far bigger than other species of the bug and have a penis two and a half times their body length - the largest relative to their size of any bug.
The new flea breed is believed to have come from Europe over the past few years and weather conditions this year have been ideal for them to breed, with a warm summer and the right balance of rain creating mild, damp conditions for them.
With the weather beginning to turn colder, experts are now warning that the fleas will begin to make their way indoors, potentially infesting sitting rooms and bedrooms across the country.
Rob Simpson, of pest controller register body Basis Prompt, said that the bugs were coming out of hibernation earlier than usual this year, meaning there would be more of them about.
He said: “Fleas which would usually remain dormant for much longer, became active sooner, leading to more prolific breeding and therefore a larger population.”
With an increase in the number of bugs comes an increase in the likelihood of being bitten by one.
Flea bites usually appear as small red spots on the skin and can be very itchy. They are commonly found on feet and legs.
Doctors advice that bites should be washed thoroughly with soap and water before applying an antiseptic cream to the affected area.