Springtime Safety Series – Fleas

By May 23, 2013 July 17th, 2017 Parasites, Summer Safety

What is a flea?

Fleas are blood-sucking ectoparasites. There are 2,200 flea species known in the world today. Only a few of these commonly infest dogs and cats. Fleas are not the same as ticks.

The most common flea that affects both dogs and cats is the cat flea, or Ctenocephalides felis. It’s dark brown or black body is about one to three millimetres long. They can also feed on people, but we’re not their first choice of meal.


Sample of an adult flea.  Fleas can be very fast moving, so it can be difficult to see the adult fleas on your pet.  It is often best to check for flea dirt.



Why do cats & dogs get fleas?

Adult fleas have specially adapted mouth parts for piercing the skin and sucking blood. More than just annoying and irritating to your pet, they can also cause significant skin disease.

Fleas love warm, humid environments. And they are determined, nimble creatures capable of Olympian feats. When they’re hungry and looking for a home, they can jump 10,000 times in a row up to 60 centimetres high. Plus their flat bodies allow them to move quickly through a pet’s fur.

You’ll usually find fleas on your pet’s abdomen, the base of the tail and the head. However, a heavy infestation can thrive anywhere on the body.

What are common signs that my pet has fleas?

You may be able to see fleas on your pet, especially if there is a large burden

Fleas are small, and just because you don’t find one on your pet, it doesn’t mean that they’re not there or that your pet is not being bitten by them!

Fleas suck your pet’s blood and can cause terrible skin irritation that will make your pet scratch, lick and bite them self. This may result in rashes, scaly skin, hot spots and hair loss

Droppings, digested blood known as flea dirt, in your pet’s coat

Above is an image of what flea dirt may look like if you part your pet’s fur to look for droppings.   If you have a flea comb, you can comb your pet (try near the base of the tail) to see if you see black debris on the comb.  To test if this is flea dirt or just dirt  put it on a paper towel then dampen the debris to see if it turns red.  If it does, then you know you have found flea dirt.


The 4 life cycle stages of a flea


Adult fleas (5% of lifecycle):

  • are the ones you see jumping around your pet’s coat
  • bite then feed on the blood of their host
  • make up 5% of the flea life-cycle
  • male and female adult fleas mate and lay eggs


Flea eggs (50% of life-cycle):

  • are not sticky and once laid quickly fall off the dog into the surrounding environment
  • can’t be readily seen with the naked eye
  • make up 5% of the flea life-cycle
  • take between 1-10 days to hatch into larvae (50% of the life-cycle)

Flea larvae (35% of lifecycle):

  • hatch from the flea eggs
  • are a small worm-like life form that move away from the light
  • bury themselves in dark places eg deep in carpet pile
  • last 5-11 days while they undergo 2 moults to become a pupa (cocoon)

Flea pupae (10% of life-cycle):

  • in a sticky impenetrable cocoon that becomes covered in debris
  • cannot be harmed by insecticides.
  • usually lasts 5-14 days, but may lay dormant for up to 6 months

What do fleas do to pets?

Adult fleas have specially adapted mouth parts for piercing the skin and sucking blood. More than just annoying and irritating to your pet, it can also cause significant skin disease. Flea blood feeding is also associated with the transmission of several infectious diseases to both pets and people.  In pets, fleas can carry tapeworm eggs, that can be passed into your pet if a flea is ingested while grooming.

What is flea allergy dermatitis (FAD)?

It’s an itchy skin disease animals develop from an allergic reaction to the saliva of fleas feeding on their blood. An affected dog will be very itchy – often from scratching, biting, licking and chewing. Their skin is usually reddened and there may be lesions and hair loss.

Infectious diseases from fleas

It’s not just your pet at risk here. Fleas can carry infectious diseases that are transmitted to humans such as:

  • Rickettsia spp. – causes flea-borne spotted fever
  • Bartonella henselae – causes cat scratch fever
  • Yersinia pestis – causes Plague, an identified agent of bioterrorism.

How can I treat or prevent fleas?

Products such as Revolution, Sentinel, Advantage or Advantix can be used to treat, control and prevent flea infestations, as well as control flea allergy dermatitis.  If you have a flea infestation, it is a good idea to combine a product for your pet with a spray for the house, to help eliminate the infestation faster.

Flea preventatives should be used year round. Your vet will be able to help you choose the right one for your pet.







  • dave brown says:

    Thanks for the info about fleas.
    Found them on our Maltese. Took him in the shower. cleaned well with a natural cleaner made from plants. Worked well. this was three weeks ago.
    Now, every day we find 2 to 5 fleas in the shower stall. kill them by spraying with the liquid soap and more are thee the next day.!!
    do you think the eggs get lodged in the drain?

    • trph says:

      Thanks for taking the time to read the article on fleas. If you are still finding fleas in the house you may need to get a house spray as well. If you are finding them in the house, they will likely be on your pet as well. You need a product that will kill all life stages of the fleas, otherwise you will have a cycle of killing the adult fleas, then more eggs hatch a few days later. Feel free to call the clinic to discuss flea life stages & treatment with our staff!

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