Do we need to fear the flea?
“All dogs have little fleas, upon their backs to bite ‘em,
And little fleas have littler fleas, and so ad infinitum!”
We often fondly imagine that the flea is a summertime parasite, and that in the depths of winter he disappears somewhere, leaving us and our pets in peace. Sadly, this is a profound mistake.
Why are fleas an all-year-round problem?
One simple answer – central heating. Fleas require a certain temperature for their life-cycle to continue, with the optimal being a little over 20C. Unfortunately, the optimal temperature for modern humans is also just over 20C, and so if we’re comfortable, probably so are our unwanted little house guests.
The adults are much less fussy of course – because they spend much of their lives clamped to a nice furry hot water bottle (called Rex, or Fido, or Puss) and can therefore endure surprisingly cold temperatures. However, if the house is warm, the flea larvae continue to develop into adults, and the infestation continues all year round.
But are they really a problem?
Most of the time, fleas are merely an irritant – their bites cause itching, but no more. However, the immune systems of many dogs and cats (as many as 40% according to some studies) see flea saliva as a dangerous foreign invader, and mount some degree of response to it. In approximately one in sixtydogs and cats, this alone is sufficient to trigger itching, scratching, discomfort and suffering as the pet develops Flea Allergic Dermatitis.
However, they pose other threats as well. Fleas may transmit Feline Infectious Anaemia to cats and are the main source of infection with the common Dog Tapeworm (Dipylidium caninum, confusingly enough a parasite of both dogs and cats).
Furthermore, in young puppies and kittens, a heavy infestation of fleas can even consume so much blood that the animal develops a serious anaemia, without enough iron in their blood to oxygenate their tissues.
To make the creatures even less friendly, the Cat Flea (Ctenocephalides felis) is far from fussy as to what, or who, it feeds on. While the Dog Flea (C. canis) is generally content to feed on its namesake, the Cat Flea will sample the blood of any warm-blooded mammal that is rash enough to come within jumping range. Cats, dogs, rabbits – even humans, they’re all just a buffet for the flea.
How do we kill them?
This great task is easier said than done. The adult fleas are relatively easy to kill – there are a wide range of medications available on prescription that are highly effective, and even over the counter drops are usually sufficient to decimate their populations.
However, the larvae are hard to find. Being soft, vulnerable, grub-like creatures, they hide themselves away in the dark, warm, sheltered places in your house – typically in the carpets and soft furnishings, the cushions and blankets, and in the dust between the floorboards. Here they feed and grow, until they are ready to pupate. Of all the fleas in your house, approximately 95% exist as eggs, larvae, or pupae hiding in the environment. This is why killing the adult fleas is insufficient – there will be another batch along in five minutes, and then another, and another.
Instead, we must be smarter than them. There are three main options for breaking the life-cycle of the flea.
Firstly, we can use environmental treatments – insecticidal sprays that kill the larvae where they cower. Unfortunately, however, the pupal or chrysalis stage is resistant to this – but we can fool them into emerging, by vacuuming the environment they lurk in. The warmth, air movement, and vibration trick the flea hidden inside into thinking that a tasty meal is walking past. Then, as they emerge, we hit them with the sprays, exterminating them.
Secondly, we can treat our pets with medications that make the fleas infertile or unable to reproduce. Indeed, many of these medications will also prevent even the larvae that have already hatched from growing to adulthood, as the larvae have the unpleasant habit of eating their parents’ and older siblings’ droppings.
Finally, we can use a modern drug that will kill the fleas so fast that they have no time to reproduce. In this case, the flea problem usually disappears with the fleas in a few weeks, unless the house is swarming with the little beasts, in which case it may take longer.
What’s the best option?
For that, we strongly recommend that you speak to one of our vets or nurses. They will be more than happy to advise you on the best way of committing widespread insecticide and protecting your pets from the Fearsome Flea.