Fleas are the most common of all external parasites found on pets. Ctenocephalides felis, the cat flea, is the most prevalent species of flea found on both cats and dogs. An infestation of fleas is both unpleasant and potentially dangerous for pets and their owners.
A flea‘s life cycle lasts anywhere from a few weeks to a month, though under the right conditions it can continue for much longer. During the lifecycle fleas go through a complete metamorphosis in three main stages:
- Adult fleas jump on to a host (e.g. cat, dog or human) and within minutes begin feeding on the host’s blood. The flea bites lead to itching and irritation and may also transmit serious diseases.
- In less than 48 hours fleas begin laying numerous flea eggs that quickly fall off the animal into the environment.
- In a few days these eggs hatch into flea larvae. These larvae dislike light and immediately crawl deep into carpets and cracks in floors making them hard to spot. The larvae spin cocoons in which they develop into pupae and when conditions are right they emerge as new adult fleas ready to jump onto a warm-blooded host and perpetuate the cycle.
A single female can lay up to 50 eggs per day. In one month, 10 females could lay up to 15 000 eggs. The pet spreads flea eggs everywhere it goes, leading to a massive infestation in the home environment. A flea can jump as far as 33 cm in one leap, so infestation of other pets and humans is easy. Fleas measure 1-2 mm making them hardly visible. For every 5 fleas on the animal, 95 are invisible in the environment (eggs falling off the animal, existing eggs, larvae and pupae in the environment). The whole home, including carpets, sofas, beds and the entire environment of the pet can be heavily infested by flea eggs and larvae, which are the seeds of future pet re-infestation. Vacuuming will only remove a small number of eggs and larvae because they are hidden deep in floors and rugs, and entwined in the fibres. Fleas can survive up to 6 months in the environment.
A single flea will bite its host around 10 times a day and ingest up to 15 times its weight in blood. Fleas also start to feed very shortly after landing on their host; 25% of fleas take their first feed within 5 minutes and 97% within an hour. This means that in cases of heavy infestation, fleas can produce anaemia in otherwise healthy animals, and in extreme cases, even death in smaller animals.
One of the main factors that allow fleas to rapidly complete their lifecycle is warmth, central heating therefore means fleas can reproduce all year round.