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Does my Cat Have Fleas

What are Fleas?

Fleas are small insects that feed on the blood of their host animal. Within their life cycle, the adult stage is spent living on and feeding off the animal. The female adult lays eggs (up to 500 per flea per day!) which roll off the animal into the environment, and then hatch into larvae. The larvae burrow into carpet or soft furnishings, then form a sticky cocoon and enter the pupae stage. The pupae can stay in this state for up to two years. The adult flea will only emerge once it senses that there is a suitable host nearby (using signals such as vibration and carbon dioxide levels). The new adult flea then uses its powerful legs to jump onto the passing animal and start the cycle all over again. When you think of the whole life cycle of the flea it is easier to understand why it can take a few weeks to several months to get on top of a flea infestation, and why it must be tackled by treating the animal and the environment.

How to spot fleas?

Cats are very good at grooming themselves, and most cats will swallow any fleas they encounter while grooming themselves. Healthy fleas are also quite active and good at hiding from human eyes. This means it can be very difficult to spot fleas on your cat, even though a significant infestation may be present. The only signs that you may come across include the cat grooming or scratching excessively, or humans in the household getting insect bites on the legs.

The best way to diagnose the presence of fleas is to comb the cat with a very fine-toothed flea comb over a clean, white surface such as a large piece of paper. This should dislodge any fleas or “flea dirt” (flea excrement). Flea dirt will look like small black specks of dirt. If you find any, place on a damp piece of cotton wool. If it is actually flea dirt it will slowly dissolve into a reddish-brown mark, as flea dirt is made up of the blood that the flea has eaten and digested. This is definitive of the presence of fleas, even if you can’t see the fleas themselves.

What are their effect on cats?

As well as being irritating for both animals and their owners, fleas can cause other potentially serious problems.

·         The cat flea can carry the larval stage of tapeworm, which will develop within the cat after they eat the flea during grooming. It is important to remember to worm your cat with a tapewormer or all-wormer if she has fleas.

·         Fleas can cause weakness, anaemia and death in kittens by feeding excessively on their blood

·         If a dog or cat develops an allergy to flea bites, they can cause serious self-trauma and develop nasty skin disease.

·         Fleas can be involved in the transmission of infectious agents between cats, and can spread Bartonella, which is a bacteria involved in “cat scratch disease” (a disease found in humans typically following a cat scratch or bite).

What are the different treatments and their effectiveness?

The best way to avoid a flea problem is to use preventative treatment on all cats, dogs and rabbits in the house. This way any new fleas your pet might pick up from the environment outside your home should be eliminated before they have a chance to breed.

If you have an existing infestation, you will need to remember that typically 95% of the flea problem is in the environment. Treating the animal will get rid of the adult fleas on the animal, but there will be thousands of eggs, larvae and pupae still developing in the environment. As the new adult fleas emerge, they will continue to jump onto the animal and feed. If the animal has been treated with something that has a residual effect, the fleas will then die, but there will be more and more ready to take their place.

A household spray will help to control the new adult fleas emerging, however nothing will kill the pupae in their sticky cocoon. The best thing to do is try and induce them to hatch, for example by vacuuming regularly, and then the new adult fleas can be exterminated via the household sprays and treatments on the animals. This can take from a few weeks to a few months.

There are many types of flea treatment for animals.

The best and most effective treatments are the ones that you would buy from a pharmacy or vet practice. There are many types to choose from, including:

·         Fipronil-based spot-ons (for example Frontline spot on, Effipro)

o   Fipronil kills fleas and ticks, and should be applied once monthly to cats

·         Imidocloprid-based spot-ons (for example Advantage)

o   Imidocloprid kills fleas and flea larvae in the animal’s surroundings, and should be applied once monthly

·         Lufenuron-based tablets/suspension (for example Program Oral Suspension for cats)

o   Lufenuron stops the larvae from developing within the flea egg so they cannot hatch, and should be given once per month to cats. This can be used in conjunction with a spot on.

·         Nitenpyram-based tablets (for example Capstar)

o   Nitenpyram kills adult fleas on the animal from 15 minutes after administration. It will only last for 24 hours so is best to use for a severe infestation in conjunction with a longer-lasting treatment.

There are other options that are only available on prescription from your vet. It is always best to discuss what the best plan for you is with your vet, based on your particular situation.

It is best to steer clear of any flea preparations to be used on your cat that contain permethrin, pyrethroids, or organophosphates.

Never use a preparation made for dogs on your cat, as these can be toxic for cats.

Although many licensed veterinary medicines contain natural constituents, “alternative remedies” products can also be dangerous for cats, as most have not undergone the safety checks that any licensed medicine would.  

Flea collars are usually ineffective and can cause skin irritation, however there are some newer formulations that are only available on prescription that are much more effective and safer.