Fleas

The most common species of flea found on dogs and cats in the UK is the cat flea known as Ctenocephalides felis. Some dogs also carry the dog flea C.canis. Meanwhile other species also carry their own versions including hedgehogs, rabbits, birds and even humans - (Pulex irritans)!

The life cycle of C.felis begins with female fleas laying up to 25 eggs per day on the host’s skin. She may lay up to 2000 eggs in a lifetime. These eggs are very smooth and soon fall off and into the environment – perhaps your house carpet. After about 2 days these eggs hatch into microscopic larvae which begin to mature according to the temperature and humidity. The warmer it is the faster they develop. The larvae head for the bottom of the carpet pile away from light and it is here they feed on old skin flakes and adult flea droppings. Eventually they change into very sticky pupae. In ideal conditions the new flea adults hatch and emerge after 12 days thus completing the life cycle. All they now need is a new host and a feed!

In cooler conditions the life cycle can take up to 6 months to complete. It is small wonder then that the problems really arise with the onset of warmer summer weather.

Recognition of the different stages can be tricky. The tiny white oval eggs are 0.5mm long and barely visible to the naked eye. Larvae are also white, 2mm long and far easier to see under magnification. Pupae are 5mm long but are well camouflaged in the bottom of carpets and bedding. Adults are 2.5mm long and brown/red in colour.

Checking for infestation is achieved by means of a simple test. Fleas are very agile and hard to see on the coat, so instead comb your pet over a white surface and collect the dander and black specks. Using moist white kitchen paper or damp cotton wool, tip the collected material on top and wait to see if any of the specks turn red or brown. If so, you are in fact seeing the digested blood from your pet appearing in the flea faeces. This is of course in addition to the characteristic itching and scratching your pet has to endure.

Severe infestations are seen as hair loss and reddening of the skin. Some unfortunate pets become very sensitive or allergic to the flea saliva. This condition, known by vets as “flea allergy dermatitis” can eventually be triggered by as little as one flea bite. It can sometimes be prevented by more regular treatment with some of the spot on preparations.

Treatments are numerous and vary greatly in their efficacy and range of effects.
There are 2 areas of attack - the animal and the environment. Purely killing adult fleas on your pet will only postpone the issue as up to 99% of immature fleas are in the environment waiting to mature. It is always advisable to firstly treat your home by thorough vacuuming and washing any bedding. You may then consider the various medications available.

Spot-on preparations are most popular. Fipronil sold as Frontline is a highly effective product available on this web site as a non prescription item. The active ingredient spreads out from the applied site on the neck and accumulates in the oily skin glands from where it then spreads back up the hair and fur. It is not systemically absorbed. It claims to kill up to 98% of new flea arrivals before they have a chance to bite and will persist for up to 5 weeks in cats and 2 months in dogs. Frontline provides additional tick control for about 4 weeks.

Frontline Combo (a prescription only medicine also categorised as ‘POM-V’) is like Frontline but also contains Methoprene which inhibits egg laying.

Advantage is another prescription spot on containing Imidacloprid which is also non systemic in action.

Stronghold (Selamectin) and Advocate (Imidacloprid & Moxidectin) are 2 other spot on products that as well as controlling fleas will also treat roundworms and ear mites. Both are available only on veterinary prescription.

Advantix (Imidacloprid & Permethrin) made by Bayer is another prescription spot on that like Advantage controls fleas but in addition it contains permethrin for tick control. The permethrin in Advantix is very toxic to cats and is for canine use only.

Tablet treatments.

Capstar works systemically and so kills fleas via the blood they ingest. They are also very safe and can be used daily. Available as a non-prescription medicine.
Program is a prescription medicine containing an insect growth regulator called Lufenuron. Program is given orally once monthly but an injectable version is available for cats.
Program Plus is like Program but also contains Milbemycin for worm control.

Household sprays include Acclaim, Staykil, RIP Fleas and Indorex. They work by killing adult fleas and also contain a hormone to prevent larval pupation. Treat all relevant surfaces but remove fish and birds from the rooms first to avoid toxicity. Always follow the written instructions on the cans. Effect will last 6 or 12 months according to brand used. All these are non prescription items.

Animal sprays, powders, collars and shampoos are freely available in many presentations but have largely been superseded in use by the more convenient and effective spot on type products.

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