Checking for fleas

Fleas

What is a flea?

There’s no other way to put it - fleas are blood-sucking ectoparasites (live on the skin surface of their ‘host’). 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.

Why do dogs get fleas?

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 dog’s fur.

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

What are common signs my dog has fleas?

  • You may be able to see fleas on your dog, especially if there is a large burden.
  • Fleas are small, and just because you don’t find one on your dog, it doesn’t mean that they’re not there or that your dog is not being bitten by them!
  • Fleas suck your dog’s blood and can cause terrible skin irritation that will make your dog scratch, lick and bite themself. This may result in rashes, scaly skin, hot spots and hair loss
  • Droppings, or flea dirt, in your dog’s coat

The 4 life cycle stages of a flea

Adult fleas (5% of lifecycle):

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

Flea eggs (50% of lifecycle):

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

The mated female flea lays 20-50 eggs per day and up to 2000 in her lifetime.

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 lifecycle):

  • 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.

Light, movement/vibrations and CO2 stimulate emergence of the adult flea from the pupa.

What do fleas do to dogs?

Adult fleas have specially adapted mouth parts for piercing the skin and sucking blood. More than just annoying and irritating to your dog, 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.

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 dog 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 and prevent fleas?

Products such as Revolution® can be used to treat, control and prevent flea infestations, as well as control flea allergy dermatitis.

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