When you’ve been unfortunate enough to become the reluctant owner of a crowd of small, itchy, blood-sucking new pets (in addition to your dog or cat), it can seem like the tide of new arrivals is never ending.
Just when you think you’ve gotten rid of them all…another flea appears, as if out of thin air!
Been a couple of months since you last saw an unwanted guest hopping about? Then surely things must be safe, at this point! Think again, friend. If you don’t keep on top of things, they’ll be back in a matter of weeks.
At this point – understandably overwhelmed with frustration – I’d forgive you entirely for asking with no small hint of irritation, where the f*ck do they keep coming from???
I’ll start with the TLRD for those who just want a rapid answer right now.
Fleas come from:
1) Other animals, originally. Usually cats or dogs, but may also come from hedgehogs, squirrels, and other (usually, but not exclusively mammalian) wildlife. Adult fleas jump from another animal onto yours, OR get on your pet via a common environment (eg, your garden, or the park).
2) You can also bring flea eggs, larvae or pupae into your home accidentally on your hands, shoes or clothes if you have visited a household that has a flea infestation.
3) Once fleas have become established in your household (by which I mean, are successfully reproducing – more on this later), new fleas can appear for MONTHS from pupae that are hidden around your home, even after you spray your house and treat your pet. This is due to an effect called “the pupal window“ (don’t worry…I’ll explain what I mean by this).
Fear not, Dear Pet Owner. All will become clear.
And beat the flea you will.
Stick with me for a quick science lesson. Trust, I wouldn’t bother if it wasn’t important.
In order to understand where those little buggers keep coming from, it is imperative to first understand the lifecycle of the flea.
The fleas which affect dogs and cats are usually cat fleas; more on this here, for those who are interested:
…but in terms of lifecycle, where they come from, and how to get rid of them, it really doesn’t matter if you have cat fleas, dog fleas or even hedgehog fleas.
The lifecycle is as follows.
Great. Very disgusting. But how does that help me get rid of them? They just keep coming back!
Well, we need to look at each stage in a little more detail, to understand how to do just that, so bear with me.
Got onto your pet, by one of the methods outlined above.
Only the female adult is able to lay eggs, and she can only lay eggs after first filling herself up with a substantial meal of your pet’s tasty blood (eww).
Remember this part for later because it’s key, OK? She can only lay eggs after a substantial meal of your pet’s blood.
So if your pet is protected with a good quality product, you’re halfway to getting rid of the fleas, since adult females will die when they bite your pet, before being able to finish feeding or reproduce.
Why only halfway?
Because of that pesky pupal window I mentioned earlier (again, stick with me, it will become clear).
Male fleas obviously can’t lay eggs, but do need to be present and mate with the females in order for egg laying to occur. Not that you can tell the different between ‘em (since fleas don’t drink beer or care for football).
Most mature female fleas will lay 20-30 eggs per day, but can lay up to 50 eggs per day. Unlike lice (nits), flea eggs are not attached to your pet’s hair. Most will be laid on your pet’s skin and fall off into the surrounding environment (pet beds, carpets, sofas, your bed etc.), and some will be laid by the adult female flea directly in the environment itself.
Obviously the take home lesson from this rather terrifying titbit, is that it is much better to address a flea infestation early on, the second you notice it, rather than letting things fester for a few days. The numbers will multiply dramatically and things will quickly spiral, leaving you with a far greater number of fleas, flea eggs, larvae and (most importantly) pupae around your home.
A KEY fact that very few people know that that fleas actually spend a LOT more time off your pet than they do on your pet…in fact, about 90% more time is spent in the environment than on your cat or dog. This is also super important to be aware of when it comes to getting rid of fleas.
Adult fleas live for a maximum of 25 days before dying of natural causes (old age).
And during this time they keep busy feeding, mating, and laying eggs.
The most boring life stage of the flea. Sit around for approx two days, then hatch.
FUN FLEA FACT: flea eggs are white, oval shaped, and only about 0.5mm in size. That’s too small to see with the naked human eye. If you can see eggs, consider if your pet could have lice instead.
Around two days after being laid in the environment, larvae hatch from the flea eggs. These larvae are maggot-like in shape (but much smaller and thinner). They start out at about 2mm in length, growing to a maximum of 5-6mm before becoming pupae.
Flea larvae live in your carpets, cracks in wooden floors and skirting boards, pet’s beds, furniture such as the sofa and beds…basically anywhere your pet goes, you might find flea larvae that have recently hatched.
Flea larvae are truly gross and survive by eating skin cells and hair fibers shed by you and your pet, as well as their own dead companions or any other organic matter. But the main component of the larva’s diet is actually the feces of the adult flea.
FUN FLEA FACT: Adult flea feces is commonly known as “flea dirt”, and the presence of this flea dirt on the comb when you brush your animal’s fur is a key way in which we can prove the presence of a flea infestation.
Because flea feces contains digested blood, flea dirt will turn red if you wipe the comb on a damp paper towel. And hey presto. You just diagnosed for sure a flea infestation.
After 5-15 days (depending how nutritious their diet was), the larvae goes into a protected state called a pupae.
This is the section you need to pay MOST attention to!
The pupae is your NEMESIS when it comes to getting rid of flea infestations.
The pupae is more annoying than the adult flea, because it’s the sole reason fleas are so bloody difficult to get rid of for good.
It can be thought of as being similar to a butterfly’s cocoon, except way more disgusting, obvs. Inside this protective shell, a metamorphosis is occurring. The vile flea larva is becoming an arguably even more vile adult flea.
You’ll find pupae – you guessed it – in the exact same places you might expect to find flea larvae. That is, absolutely everywhere your pet has been.
Here’s where things get interesting, and what you really need to know in order to successfully address that pesky flea infestation:
Whilst the flea is in it’s “pupal” stage, it is invincible.
Yes really. Like a supervillain.
Flea pupae are heavily armored and in a highly protective state. You cannot kill flea pupae with flea spray or flea bombs; although, if an adult flea hatches and you sprayed recently enough, the newly-hatched adult will die or – depending on the type of spray you’ve used – be unable to reproduce.
Likewise, flea treatments that you use on your pet (for example, spot-ons, tablets, collars and sprays) will not kill pupae because obviously a pupa is not going to be biting your pet or coming into contact with that flea treatment.
The pupa is just chilling, in your carpet or your skirting board, or under the rug, biding it’s time, waiting to hatch and re-populate your home with fleas just when you thought you’d finally gotten rid of them.
And get this. Pupae can wait THREE MONTHS before they hatch – on rare occasion, even longer!
This means you need to keep every pet in your household protected against fleas for at least 3 months, in combination with spraying or bombing your home, and frequent hoovering and cleaning of bedding/soft furnishings, to successfully rid your home and family of a flea infestation.
There are however several things you can do to encourage the pupae to hatch much more quickly than three months. Broadly speaking, pupae are stimulated to hatch by warmth and humidity, and most importantly by movement.
How To Get Rid Of A Flea Infestation
I would advise the following protocol to eradicate a flea infestation:
- Ensure all pets in the household are strictly kept up to date with their flea protection, using a product with very little resistance in the flea population such as bravecto or prinocate. I recommend six months of continuous protection as a minimum, but even better just keep them up-to-date forever going forward.
FUN FLEA FACT: like bacteria can become resistant to antibiotics, fleas have developed resistance to a number of older flea products, including many of those available over the counter. Your best bet is to use a product prescribed by your vet.
- Thoroughly vacuum your entire home.
- Spray or bomb your house using an appropriate product such as R.I.P Flea spray, or Indorex spray. Be sure to read instructions carefully and be aware that you will need to remove all living creatures including yourselves, pets and fish from your home when you spray for a period of time (usually several hours).
TIP: If a complete evacuation is impossible, consider splitting the house into two halves, and doing the job over two days, making sure the half y’all are living in remains very well ventilated and very well sectioned off from the sprayed half.
- 24 hours after spraying, vacuum the entire house again (sorry, it’s got to be done). The movement encourages the pupae around your home to hatch, so that the adult fleas come out of the pupae and die because of the spray and/or from biting your protected pet.
- Continue to vacuum twice weekly for a further two weeks, and wash bedding and soft furnishings weekly.
- Also, it can be helpful to hang wet towels on warm radiators in every room of the house to increase the humidity. This also encourages those nasty little pupae to hatch so that they can DIE 🙂
- Ensure your flea-treated pets have access to every room in the house during this time, because we want pupae to hatch into adult fleas, and we want these to bite your pet once and – you guessed it D.I.E., (which they will, before they can reproduce, so long as you’ve kept your pets protected).
- Sit back, grab a coffee, and breathe a massive sigh of relief. Fleas are now gone.
FYI, if you want to learn even more about the pupal window, I think the RIP Flea website also explains it really nicely, so here’s a link to them (no, they’re not paying me. But I know from personal and professional experience that their product works phenomenally well, when correctly used);
You may also be interested in informing yourself on the health risks to you and your family if you are currently living with a flea infestation.
The following resources applied to the United States, however, the information regarding Cat Scratch Disease and Tapeworm applied in the United Kingdom too.
We don’t have plague or flea-bourne typhus here in the UK though. Sorry America, that’s just you.
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