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What do fleas look like?

Cat flea (Ctenocephalides felis)

Flea on a white surface

What do fleas look like?

Fleas are a few millimeters long and wingless, but they have back legs that are modified for jumping. These nasty little parasites can jump up to 30 cm high, which allows them to jump from the ground and onto pets with ease.

Fleas are small (about 3 mm long), brown or reddish brown insects that have flat bodies and feed by sucking blood from animals and humans, causing itchy bites. Although fleas are tiny, they can make your dog or cat’s life miserable. Once on your pet, fleas can bite up to every 5 minutes leaving your cat or dog itchy, sore and uncomfortable. Flea bites look like small red spots that often appear in lines.

In Canada, flea populations usually peak in the summer and fall seasons, but warm temperatures and high moisture can generate an ideal environment for fleas year-round. Fleas lay eggs which roll off the pet and into the home.

How to tell if your dog has fleas?

Seeing a flea on your well-cared dog or cat can be a horrifying experience. Here are some signs you might look for to determine if your pet has fleas:

  • Little dark spots that move in the fur
  • Small black particles (flea droppings) or white specks (flea eggs) on the pet or bedding
  • Pet or family members are experiencing an itch from flea bites
  • Reddened patches and irritation on your pet’s skin
  • Excessive licking or scratching
  • Hair loss

If you are not sure you have a flea problem, use a flea comb on your pet’s back, tail and haunches. The flea comb may catch fleas or flea dirt (feces). To distinguish flea dirt from other dirt, wet it with a little water. Flea dirt will dissolve into a red-brown colour.

Flea cat infection

Clinical signs of flea allergy dermatitis (FAD) in a cat

Keep in mind that you might not actually see fleas on your pet. Cats are good at grooming away fleas and the fleas may move too quickly for you to be able to see them when you look through your pet’s fur.

How do I know if I have fleas in my home?

You only need to bring one flea inside your home to start an infestation. One female flea can produce enough eggs to create a real problem. Fleas live on wildlife like squirrels, rabbits and racoons, as well as cats and dogs. When your pet is outdoors, fleas from the eggs left behind by other animals can jump on your pet. Your pet doesn’t even need to come near another animal to be infected. Once on your pet, they feed on his blood and start laying eggs. A single female flea can create a serious infestation in just a couple of months. As your pet runs and plays around the house, they drop flea eggs onto floors and furniture, creating an infestation. Wherever your pet goes, flea eggs go too.

Advantage® II is safe for puppies and kittens, as well as cats and dogs. Advantage® II is approved for puppies 7 weeks of age and older and cats 8 weeks of age and older. Please speak to your veterinarian for solutions for animals less than 7 or 8 weeks old, respectively.

Flea lifecycle

There are four stages in the lifecycle of a flea. Understanding the four stages of the flea life cycle can help you treat a flea infestation and prevent new infestations in the future.

  • Eggs. Adult fleas lay eggs on pets and they fall into the home environment as pets move around the home. Flea eggs are very small and white. A single female flea can lay up to 50 eggs in just one day. Eggs are light and fall off the pet, being easily distributed throughout the home.
  • Larvae. After 2-10 days, the eggs become larvae that feed on feces from adult fleas as well as dead flea larvae. Larvae move away from light and move deep into carpets, upholstery, cracks in hardwood floors, and even under baseboards. This stage lasts about 5-11 days.
  • Pupae. The larvae create a pupa or cocoon. Inside the pupa, the larvae mature into an adult. The flea is protected from most premise treatments as they are located beyond the reach of most sprays and seem to resist most cleaning efforts including steam cleaning. The flea takes 1-3 weeks to mature in the pupa and remains in the pupa until a food source (pet) is detected nearby. The flea can wait for up to 6 months and only hatches when triggered by heat and vibrations indicate a host is near.
  • Adults. Young adults emerge from cocoons when conditions are favourable and begin feeding within seconds of finding a host. Once fleas start feeding, they continue to feed regularly and are dependent on their host. Fleas removed from the cat or dog, without access to blood, will usually die within 4 days. As fleas need a constant food supply, movement of fleas between animals occurs much less commonly than infection from the environment.

Flea life cycle

Development stages of fleas, from eggs to adults

The entire flea life cycle takes approximately 21 days, but it varies depending on temperature and moisture conditions of the environment (warm and moist are optimal for flea development).

To most effectively eliminate a flea infestation, you have to disrupt their life cycle. Advantage® II kills all life stages; adult fleas, eggs, and larvae. This prevents eggs immature fleas from developing into new adults. Fight the misery of biting fleas. Many other products are systemic, they are carried in the pet’s bloodstream and only work when fleas bite and consume blood. Advantage® II spreads on your pet’s fur, killing fleas through contact, so fleas don’t have to bite your pet to die.

How can fleas affect your pet’s health?

The health of pets is always under threat from a variety of parasites and the diseases they may transmit. Effectively controlling parasites is critical to keeping pets healthy.

Parasite bites are not just painful and uncomfortable for dogs and cats; they can also transmit a number of diseases to both animals and humans. Continuous scratching can lead to pet’s skin becoming sore and can also result in hair loss.

Fleas can cause serious diseases in pets, such as flea allergy dermatitis (FAD), which is an allergy to flea saliva that creates a rash. If an animal is allergic, the itch can lead to further damage and can require a visit to a veterinarian for treatment to help the pet recover.

Heavy flea infestations can lead to anaemia in cats and dogs, because fleas have consumed a significant amount of the pet’s blood. Puppies and kittens are especially at risk of a dangerous drop in the number of red blood cells in their body. Common signs of anemia include pale gums and lack of energy.

Fleas can also transmit tapeworms. Pets can become infected with tapeworm if they accidentally ingest a flea while they are grooming. In fact, cats ingest up to 50% of fleas. Pets suffering from worms may experience loss of appetite and scooting, but in many cases there will be no visible signs of infection. Although tapeworm are not generally zoonotic (unless you accidentally swallow a flea), other worms are – meaning they can be passed on to humans. This is why you should always wash your hands after handling a pet.

Fleas carry some bacteria than can cause disease in human beings, such as Bartonella henselae. This bacterium is present in flea dirt and responsible for cat scratch disease (CSD) which can be transmitted from cats to humans if a cat with fleas bites a human or through petting the cat. Although this disease is not fatal to humans, patients can experience considerable muscle pain, lack of appetite and chills. Dogs can also be infected with different Bartonella species from fleas, lice and ticks, showing symptoms that include lameness, vomiting, liver and heart disease.

Dog and cat lying on a blue sofa

How to get rid of fleas on your pet?

Treating your pet with Advantage® II monthly, according to the product label, will effectively kill fleas and treat a flea infestation. While treatment of the environment is not needed when Advantage® II is used, you can put pet beds in the dryer to kill developing fleas. Vacuuming can encourage developing fleas to hatch. Once they touch a treated pet, Advantage® II will take care of the rest. Pay attention to low traffic areas that pets may not frequent.

The less parasites bite, the better. Flea and tick pills or chews work by getting into your dog’s bloodstream, but that means for a flea to actually die it must bite your pet. Advantage® II is different; it is evenly distributed over your pet’s skin, working topically to kill fleas through contact, no biting required. It is a fast, effective and easy to apply spot-on (topical) treatment. It is recommended that Advantage® II is used once a month to treat and prevent flea infestations.

Advantage® II breaks the flea life cycle and controls fleas within 24 hours. It is also waterproof. Treated pets can swim 48 hours after application and can also be bathed once per month with a non-medicated pet shampoo.