The Flea Life Cycle

Regardless of where you live, all pets are susceptible to picking up fleas. Without regular flea treatment for your dog or cat, a single flea can very quickly turn into an infestation. In order to effectively protect your pet and home, it’s crucial to understand the flea life cycle. Fleas have four life stages where they exist in very different forms. As a result, a combination of different approaches and treatments are required to tackle a flea infestation effectively. In this blog, we’ll detail what happens during the flea life cycle and explain how the best approach to getting rid of flea infestations takes these four life stages into account.

1) Flea Eggs

In the first stage of the flea life cycle, the female lays eggs in her host’s fur. The female flea can only reproduce having had a blood meal from her host. These eggs are white and are marginally smaller than a grain of sand in size. They represent around half of the entire flea population.

A typical female flea can lay up to 40 eggs per day. As your pet moves around, these eggs will fall off of their body and into the environment around them including onto furniture, carpets and other soft furnishings. This enables the eggs to develop within the home itself as well as on your pet. This is why it’s important to treat the entire home to get rid of fleas, not just your pet.

Eggs can hatch as quickly as two days later, up to a couple of weeks later. How quickly flea eggs hatch depends on the conditions around them: if it’s warm and humid, they’ll hatch sooner than if it’s cold and dry.

2) Flea Larvae

Flea larvae emerge from the hatched eggs. This is the second stage of the flea life cycle. Flea larvae are translucent white worm-like creatures that are about a quarter of an inch long. They make up around 35% of the flea population.

In order to grow and develop, flea larvae eat pre-digested blood (known as ‘flea dirt’) from adult fleas as well as other organic material in the environment. After 5-20 days, if the conditions are right, flea larvae will make cocoons for themselves.

3) Pupae

Fleas in their cocoons are in the pupae stage of the flea life cycle, which is the last stage before they become an adult flea. Pupae make up around 10% of the flea population.

These cocoons are very protective: not only are they sticky, allowing them to resist vacuuming, but they are also not vulnerable to most chemicals, including those in flea treatments. Fleas can also survive in their cocoons for many days, weeks or even months if the conditions are not right for them to emerge.

During this time, the larva will develop an exoskeleton and transform into an adult flea. The adult flea will emerge from its cocoon when it senses that a host is nearby. It will be alerted to this by the following triggers:

  • Vibrations, which can be caused by your pet walking by
  • Increased levels of carbon dioxide
  • Body heat

4) Adult Fleas

Once adult fleas emerge from their protective cocoon, they will begin to feed on their host within just a few hours. Very soon after she has fed, the female flea will reproduce and begin laying eggs – and so the cycle continues.

Adult fleas are generally the ones you actually see – they are small and thin with six legs, and they are dark brown/red in colour. Their hind legs allow them to jump incredible distances, which is how they are able to leap onto a host so quickly. Adult fleas only make up 5% of the whole flea population.

What is the Average Lifespan of a Flea?

The answer to this question varies a lot, depending on the flea’s environmental conditions. If the flea has a consistent food supply (i.e. a cat or dog is nearby), and the temperature and humidity levels are right, an adult flea can live for as long as 100 days. However, without a host for food, a flea will die in just a few days from starvation.

Having said this, fleas in other stages of the life cycle can survive for very long periods of time. Fleas can remain in their cocoons in a dormant-like state for as long as five months.

How Long Does it Take to Break the Flea Life Cycle?

It can take anywhere between 2 weeks and 3 months to break the flea life cycle, and be sure that they are completely gone.

Because fleas go through various different life stages, we need to target all of them in order to successfully break the flea life cycle.

Treating your pet with flea treatments is an essential part of the battle, but isn’t enough on its own. Eggs will inevitably drop off your pet and be transferred into your home, making it vitally important that you also treat these areas too to prevent them developing into adult fleas and continuing the cycle.

How to Break the Flea Life Cycle

There are three main stages to breaking the flea life cycle, and getting rid of them from your home for good.

First, you’ll need to regularly and thoroughly vacuum your home and wash all soft furnishings including bedding, sofa cushions, dog toys and curtains on a hot temperature. This will get rid of most flea eggs, larvae and pupae.

Your pets will also need to undergo flea treatments, which can be administered orally or topically. This will kill adult fleas.

Finally, you’ll need to address any remaining fleas in the pupae stage. Fleas in the pupae stage are the most difficult to eradicate, as they are able to survive the treatments that kill eggs, larvae and adult fleas, and it’s difficult to guarantee vacuuming them all up since they can remain well hidden. You can encourage them to emerge from their cocoons by using a humidifier and increasing the temperature in your home. Once they’ve all emerged, they can be killed with household flea sprays and foggers.

For more information on how to break the flea life cycle and eradicate fleas from your home, read our blog ‘How to Get Rid of Fleas’.

Wrapping Up

Fleas exist in 4 distinct forms during their life cycle, and understanding this is essential to eradicating fleas from your home. Eggs, larvae, pupae and adult fleas all need to be addressed when getting rid of an infestation. This means that as well as treating your pet, your home needs to be thoroughly cleaned over several weeks, in order to make sure they’re gone for good.

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This blog was checked by Karin Volker, MRCVS

Biography of Animed vet, Karin Volker, MRCVS