Fleas are more than just a nuisance. They’re gross—and they can make life miserable for you and your pets. Fleas are also carriers for numerous diseases such as typhus and tapeworm infection. During the Black Death plague of 1348 to 1350, fleas carried by rats bit their human hosts and literally injected them with disease. Typhus, another disease transmitted from rats to humans, has been known to occur in the southwestern and Gulf Coast states by the oriental rat flea (Xenopsylla cheopis).
Luckily, the most common flea species found on dogs and cats today is the not the rat flea, but the cat flea, otherwise known as Ctenocephalides felis. We may occasionally encounter the dog flea, Ctenocephalides canis, but despite its name, the cat flea is the most common type of flea to infect pets including dogs, cats, ferrets, and rabbits.
FACT: More than 2,200 species of fleas have been identified worldwide!
In order to control or prevent flea infestations, an understanding of the flea cycle is necessary and absolutely essential. Without a complete understanding of the flea cycle it will be difficult if not impossible to get rid of fleas in your home as well as kill fleas that infect your pets. In fact, this would be like going to war without a battle plan. Sure, you might have the weapons but if you use the weapons ineffectively you’re only wasting valuable resources. You might win the battle but you must certainly aren’t going to win the war.
From egg to adult, the average life cycle of the cat flea will be between 20 and 35 days. However, under certain environmental conditions the life cycle can last up to one year or longer. Fleas are very good at adapting to adverse environmental conditions. If certain parameters aren’t ideal, fleas will often “hibernate” during the pupae stage for weeks or months at a time until things appear more favorable. This is why new home owners and apartment dwellers are often greeted by a flurry of flea activity. The pupae stage is nearly indestructible and the adult flea will only emerge from its cocoon until a potential host is detected nearby.
The flea life cycle is influenced by temperature and moisture conditions. An ideal temperature for fleas is around 75 degrees F with optimum humidity around 80%. Under less favorable conditions, the life cycle will take longer. But as long as conditions are favorable, flea reproduction can take place indoors all year long, while outdoor reproduction is limited to warm-weather months. At all life stages, fleas can’t survive temperatures above 95 degrees F or below 34 degrees F.
Some pet owners are surprised when they find adult fleas living on their dogs and cats during the winter months, but your house is a perfectly suitable environment for fleas to grow and develop in during the winter months. They don’t need sunlight or fresh air to survive and reproduce–only a blood meal!
Understanding the Flea Life Cycle
The life cycle of the flea consists of four stages: egg, larva, pupa, and adult. An important thing to keep in mind is that the adult stage is the only stage that is visible to the naked eye and comprises only 5% of the total flea population in your home. You may be upset to find one adult flea on your pet, but keep in mind that one visible adult flea is probably equivalent to thousands of microscopic eggs, larvae, and pupae that are living in your pet’s environment (your house). The adult stage is also the only stage of the flea cycle that lives on your pet.
Flea reproduction occurs on the host animal. Once they find a host, adult fleas begin feeding within seconds to minutes. Within 24-36 hours of taking their first meal, female fleas begin to lay eggs at a rate of around 40-50 eggs per day. Without a blood meal, fleas are unable to reproduce.
Because flea eggs aren’t sticky, they fall off your pet and into your home or yard. Depending on environmental conditions, the eggs hatch into larvae 2-14 days later. Larvae prefer to stay out of direct sunlight (they are killed at 95 F) and will burrow into any available material, including bedding, carpeting, furniture, and cracks in the floors. Woods floors are a particular favorite. They don’t have legs but move around using the bristles on their body, much like a caterpillar.
The larvae grow by molting and shedding their skin (three times to be exact). Under adverse conditions, this growth process can take as long as six months but usually lasts only 8-24 days under favorable conditions. During the growth process larvae feed on a wide variety of organic debris including dry feces from adult fleas, pet feces, and particles of pet food.
At any given time, about 35-57% of the fleas in someone’s house are in the larval stage. The larvae may also ingest tapeworm eggs as they graze on flea feces lovingly deposited for them by adult fleas. After the third molt, the larva spins a silk cocoon, where it can stay for as long as a year if it needs to—but usually will emerge within a period of 5-7 days.
The cocoon is very sticky and attracts a lot of dust and debris. While the larvae can be somewhat fragile, the pupal cocoon is nearly indestructible. While in the cocoon, the pupa develops into the adult flea we’re all familiar with. However, the pupa will remain in the cocoon as long as its need to, even up to a year, until it waits for the right time to emerge.
The pupa will only emerge from the safety of the cocoon if it detects a host nearby. Amazingly, they are able to detect heat, vibrations, and exhaled carbon dioxide from inside their cocoons. Once stimulated, the adult flea exits the cocoon and seeks out the host. This marvel of science is the main reason why many people return home from vacation or move into a new home where it seems lots of hungry fleas have been waiting for them.
Quite literally, the fleas have been waiting for them—safely tucked away in their cocoons! Many boarding kennels are blamed for infesting dogs with fleas when what really happened was that the pupae waited to emerge while there was no host present and then all emerged suddenly when the dog arrived back home.
Once it finds a host an adult flea will never leave unless physically forced to do so. If left undisturbed, the female flea can spend its entire reproductive life on one animal host, laying 2,000 eggs or more.
FACT: At any given time in a household, only 5% of the flea population is in the adult stage . This means that 95% of fleas are not living on your pet, but in your house.
Killing Fleas is Not as Difficult as You Think
You’ve probably heard horror stories from people with severe flea infestations in their home. As a licensed veterinarian technician, I’ve talked to many distressed pet owners who are at their wits end because they’ve tried every flea product under the sun and can’t seem to get rid of the fleas on their pets and in their home. Usually the problem always comes down to the fact that the person doesn’t have a complete understanding of the flea cycle, is using the wrong flea products, or is using the best flea products ineffectively.
There is no need to use old-fashioned flea bombs and flea sprays to treat your home. If you want to tackle your flea problem head-on, the only weapons you need are a vacuum and effective flea control products purchased from your veterinarian. When it comes to killing fleas, OTC flea control products are a complete waste of money in my opinion. Not only are the main ingredients less effective, they are potentially more dangerous to you and your pet. The active ingredients used in veterinary-recommended flea products such as Frontline Plus are toxic only to fleas. Active ingredients found in flea products sold in pet stores, grocery stores, and other convenience stores contain ingredients that are toxic both to insects and mammals. They may be cheaper–but there’s a reason why.
You will also find Frontline Plus sold online and at pet stores. Merial, the company that manufacturers Frontline Plus, states that, “It is Merial’s sales policy to sell our small animal products only where a veterinarian/client/patient relationship exists. Merial believes that the veterinarian is the only professional qualified to serve the health care needs of pets, the concerns of their owners and the appropriate use of our small animal products such as FRONTLINE Brand Products.”
So, any other retailer selling the product is doing so against the wishes of the manufacturer. Most likely, a licesned veterinarian purchased the product from Merial, and then re-sold it to a third party.
Just keep in mind that while some of these stores and online retailers are probably selling the products cheaper than what you’d find at the vet clinic, we really have no idea how these products have been shipped or stored. If not stored at room temperature they quickly lose their potency and effectiveness. Your best bet is to ask your veterinarian if they can match the prices you find at the store and online. That way you can make sure you get the best product possible and save money both at the same time.
As far as products go, one of my favorite topical flea control product for both cats and dogs is Frontline Plus. Even after 10 years it continues to work well as long as clients know how to use it. There are a few things you need to know before applying it to your cat or dog.
How to Use Frontline Plus
1. When dealing with a flea infestation, all pets in the household need to be treated.
2. In order to break the flea cycle, all pets should be treated for 3 consecutive months (once every 30 days for a period of 90 days). Pets do not need to be bitten by the flea in order for the product to work. Fleas will die within 12 hours of coming into contact with your pet’s haircoat.
3. Your pet should not be bathed within 48 hours of applying the product, either before or after. Frontline works via the oil glands of your pet’s skin. In order to reach the oil glands which are located beneath the surface of the skin, oil must be present. If your pet has recently had a bath, these oils will not be present in large enough quantities. Also, if your bathe your pet too quickly after applying the product, it will not have enough time to reach all the oil glands located on your pet’s body.
A brochure published by Merial states, “When applied, Frontline moves from the point of application (within 24 hours) to the oil glands all over the pet’s skin. These oil glands replenish the skin and hair coat with Frontline. Because the product remains in the oil glands in the skin, it’s waterproof. This reservoir explains why Frontline provides such a long period of effectiveness and keeps working even when your pet is exposed to water, sunlight or shampooing.”
A lot of pet owners get confused because they hear Frontline is waterproof but are also told to wait 24-48 hours before applying the product or to let the pet get wet. This is because the product needs a certain window of time to redistribute itself to all of the oil glands located on the body. If your pet is not dry at the time Frontline is applied, there will be no oil present on the surface of the skin to deliver the active ingredients to the oil glands.
4. Be sure to apply the product to the skin, not on top of the fur. Avoid the collar area so it doesn’t absorb any of the product and apply in one single location between the shoulder blades. Make sure the entire pipette is used. Several squeezes may be necessary to apply the entire dose.
How to Get Rid of Fleas in Your Home
While you’re killing the adult fleas on your pet with Frontline, you probably want to help eliminate the number of eggs, pupae, and larvae infesting your home. Don’t waste money on flea bombs and sprays. A recent study performed by entomology professors at the Ohio State University found that vacuuming fleas from carpeting kills 96% of adult fleas and 100% of pupae and larvae. That’s a huge blow to the flea life cycle!
Despite the protection of cocoons and exoskeletons, the force of the vacuum’s brushes combined with fans and strong air currents is enough to wear away at the cuticle of a flea, causing death. In addition to using a safe flea control product on pets, the researchers suggest that pet owners who are facing a flea infestation should vacuum their carpets and other flooring every 2 days for at least a month.
In addition to Frontline, other flea control products that I highly recommend for cats and dogs include Capstar and Sentinel. Capstar (nitenpyram) is the product we reach for at work when we find a stray kitten or any other pet that is severely infested with fleas. Capstar is a tablet and begins to work within 30 minutes and provides almost immediate relief to the animal. However, it only lasts for 24 hours so you need to prepare for reinfestation with either another dose of Capstar or a longer-lasting product.
Sentinel is a combination flea control and heartworm preventative. Sentinel is basically a combination of two products–Program (lufenuron) and Interceptor (milbemycin oxime). Lufenuron doesn’t kill adult fleas in the same way as Frontline, but instead makes adult fleas sterile and unable to reproduce. Because the product is absorbed systematically, the flea has to bite your pet in order for it to work. However, one of the most effective treatments you can use for eliminating a severe and persistent flea infestation is combination of both Capstar and Sentinel (or Program). I give both of my dogs Sentinel during heartworm season. I’ve never had to deal with a severe flea infestation in my home and I prefer to keep it that way. If they bring in a flea or two from the outdoors there’s no need to panic because I know those fleas will be unable to reproduce.
What About Natural Flea Products?
If you’re dealing with a severe flea infestation, I don’t recommend using “natural” flea products. I’m sure I’ll get a lot of criticism for my opinion, but it is what it is. I’ve seen what works and that’s what I’m going to stick with. Other people are certainly welcome to do the same. If you’d like to give the natural approach a try, please don’t let me stop you. However, you just might want to bookmark this page for future reference.
Related post: How to Get Rid of Fleas on Ferrets