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Just mention the word "flea" and cat and dog owners' worry. Of the many types of flea, only a few are serious pests and nearly all those found on dogs and cats are so called "cat fleas" - despite their name they are happy living on many animals including rabbits, squirrels and hedgehogs as well as cats and dogs (they will also bite humans as many pet owners will know)
A flea bites for a meal of blood and when feeding it injects saliva to stop the blood clotting - it is this that causes irritating spots or the more severe "flea allergic dermatitis".
As well as a discomfort to both animals and people, fleas are also a risk to health so their control is important. The main problems seen in pets are:

  • Flea allergic dermatitis (a distressing skin disorder)
  • Loss of condition
  • Skin infections (through scratching)
  • Transmission of tape worms
  • Anaemia (which can lead to death) in young or ill animals
  • Transmission of viruses and bacteria.

These tough little insects have been around since the time of the dinosaurs and controlling them is not easy. To understand why, we need to know how a flea lives-.

Adult fleas live on the "host" animal (in this case our pet!) and it is here it mates and lays eggs. It is only the odd adult flea that falls off to bite us or another animal. Many are killed during grooming but if they avoid being eaten in this way they can live at least 4 months on our dog or cat. During this time the females lay up to 50 eggs a day. The eggs fall off wherever the pet goes, in particular where they sleep. These eggs are about the same size as a grain of sand and often end up in small cracks and crevices in carpets and floors. Each egg hatches and out comes a "larva", this charming creature looks like a small maggot with a few hairs- it is very good at burrowing and if disturbed e.g. by the vacuum cleaner, it winds itself around the nearest object such as a carpet fibre making it impossible to remove. What does it eat? - it feeds on things such as pet dandruff and flea dirt that falls off the pet into the carpet. It also eats tapeworm eggs that stay inside the flea as it develops and if eaten as an adult flea during grooming these eggs are released to infect our pet.
The larva grows and develops a hard case becoming a "pupa". This is a very tough stage, nearly impossible to kill and worse still, it can wait at this stage for over a year before hatching into an adult flea ready to jump onto a passing dog, cat (or human) to start the whole thing off again (mating, laying eggs etc. etc.)
It takes only 15 days (or as long as 18 months) for a new egg to become an adult flea. In 6 months one flea on your pet will typically become 100 new fleas. Sounds impressive? but there will be a further 9000 fleas as eggs, larvae or pupae in the carpet, bed and furniture waiting to develop into adult fleas. So seeing a few fleas on your cat or dog means many more growing in the environment.

So how do we get rid of them? As said, they are tough and no method is perfect. We have to balance safety, effectiveness, ease of use and cost.
Looking at the way fleas develop we can see treating the bedding, carpet etc. is as important as treating the pet and remember, a pupa can rest for over a year so treatment cannot be a quick fix.
There are a large number of preparations for flea control, some good, some not so good.

  • Aerosols are commonly used as they are relatively cheap and quite easy. The disadvantage is the difficulty in estimating the dose given and often the user breathes in as much as the animal receives! Pump action sprays are more accurate and can be very effective but also tend to be more expensive.
  • Other methods include tablets or injections to stop flea development, these are very safe to animal and owner but are expensive and best used to prevent rather than treat a flea infestation.
  • Powders are generally poorly effective but some are very safe to use on young animals.
  • There are droppers - the liquid contents dripped onto the back of the neck (where they can't be licked off) Some are very good and can be long lasting but this depends on the chemicals used - this is true also of shampoos and mousses.
  • Flea collars also vary in how effective they are, again it depends on the chemicals used (and some have been associated with skin reactions).
  • Various herbal remedies have been tried, their effectiveness is unclear but they are unlikely to be as reliable as conventional products.

As owners we must be careful, many of these products cannot be used together, some can be used only on cats or only on dogs, some cannot be used on animals with certain skin problems and some need quite accurate dosing to be safe. The best advice has to be "ask your vet" but do mention how important to you cost or ease of use is - many dogs (and most cats!) would be difficult to shampoo regularly and many, many cats panic at the sound of an aerosol.

Here at the Destitute Animal Shelter new boarders often arrive carrying a few (and sometimes many more) fleas. Aerosol sprays are commonly used to rapidly kill the adult fleas but other methods are used if the individual cat or dog needs it.
Reducing those fleas developing in the environment can also be done in various ways. So called "flea traps" sound great but aren't, powders are a little better but not as effective as some of the aerosols. Even these vary - the best of them stop most fleas developing and kill off any adults that do emerge. Some will even last up to a year after a single application.
As said, fleas are tough, they have been around for millions of years and we will never be free of them. We have to learn to "manage" them. Their only real weakness is that they like things warm. We may moan about the weather and even though it won't get rid of them, the cheapest way to reduce flea numbers is to turn off the heating!

We are grateful to Mike Nolan at Darley House for this article and can only repeat what he sags, "for effective treatment see your Vet". In our experience most supermarket type products do not do the job.

The products that we use at the Shelter are:

Nuvan Staykill - For treatment of areas where fleas or other parasites might be hiding/living.

Frontline Trigger Spray - For ticks and severe infestations of fleas.

These are all good products but must be used under veterinary supervision. There are some good herbal remedies but they are not up to what we need in a kennel environment.