Flea Infestations

Flea infestation can be extremely unpleasant and may cause severe discomfort for pets.  Flea bites can lead to more serious allergies resulting in itchy, crusty lesions, (Flea Allergic Dermatitis) and hair loss. Fleas also carry and can transmit infectious agents (e.g. tapeworms, Bartonella which can cause cat scratch fever).

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  • Fleas can cause many symptoms which can vary widely in severity

    Clinical signs associated with fleas can vary, and some cats may show little or no clinical signs even if they have heavy flea burdens.

    The most common sign seen is itching, which can be very severe. This may lead to a rash, inflammation and/or hair loss. If your pet is itchy and scratches, bites, rubs or licks its skin or coat frequently, one of the first things to consider is a flea infestation. Signs are classically seem on the back half of the body including the tail head, thighs and  abdomen. 

    Although fleas may only cause a small amount of irritation to some pets, anaemia may develop in some cases, especially in young kittens. Fleas may also carry infectious agents that can be transmitted to pets and even to people, such as tapeworm and Bartonella.

    Some cats react very strongly to flea bites which may be due to an allergic reaction, known as 'Flea Allergic Dermatitis' (FAD). They react to protein in the flea saliva to which they are exposed when the flea feeds. These cats may be troubled by particularly persistent itching or 'overgrooming', which causes a severe amount of irritation and discomfort.  FAD is the most common hypersensitivity disorder seen in cats.  

    Fleas are small, narrow, dark brown creatures and can be detected crawling or jumping around in your pet’s fur, but may be difficult to see especially in pets which are meticulous groomers or have long thick coats. You may also see tiny black specs in your pet’s fur, this is flea faeces, made up of digested blood.

    Summary of signs

    • Scratching, itching, skin licking
    • Hair loss, crusts
    • Bacterial skin infections
    • Flea Allergy Dermatitis (a hypersensitivity to flea saliva)
  • How can you tell if your pet has fleas?

    Fleas are one of the most common reasons for your pet to scratch, bite or lick its fur more than usual, although some pets show very few signs even if they have a heavy infestation. Occasionally you may be able to see fleas or flea dirt in the coat. 

    A definitive diagnosis requires finding adult fleas and/or their droppings. However because they are so small, fleas are often difficult to detect and removing them can be more difficult than you think. You can check for fleas by running a special flea comb through your pet‘s fur. Along with looking for fleas, check also for tiny reddish black flea dirt. To confirm this, the flecks can be placed on a white wet paper towel: you will see reddish brown spots appear (due to the digested blood present in the flea dirt).

    Flea Allergic Dermatitis (FAD) is  the most common hypersensitivity disorder in cats. Affected animals generally manifest their pruritus (scratching) on the back half of the body including the tailbase, thighs and underneath the abdomen. A diagnosis of FAD is made by considering several pieces of information including the history, clinical signs and the presence of fleas or “flea dirt”.  Intradermal skin tests are available but response to therapy with a complete flea control program for a number of months is very commonly used.

  • It is essential to adopt the right strategy to prevent flea infestation by consulting your vet for advice.  Although it has advanced dramatically during the past few years, successful flea control can still be challenging. There are several once-a-month products for treatment that either are applied on to the animal‘s back or are given orally.

    Because the majority of the flea’s life cycle is actually spent off the host, it is important to consider the need to treat both the pet and the environment. Pet owners should vacuum thoroughly, launder bedding and consider using a spray that helps control the environmental life stages for quicker results. Some products applied to the pet are also effective in helping to manage the environment. While some commercial products are effective against more than one life stage of the flea, none effectively kill the pupae stage. 

    The Treatment for fleas must therefore focus on three points:

    1.  Kill adult fleas on your pet quickly: Choose a flea treatment that kills fleas quickly on your pet to minimise the itching, irritation and risk of disease transmission caused by adult fleas.

    2. Kills flea eggs to stop further contamination of the environment: flea-infested pets continuously spread numerous eggs. Remember, 10 fleas can lay up to 15,000 eggs in one month! To stop further infestation of your home, you should select a flea treatment which also kills flea eggs.

    3. Kills flea larvae in the contaminated environment: 95% of flea stages are found in the environment. A flea treatment that also kills the flea larvae and existing eggs will help you to get rid of a flea infestation.

    95% Fleas live in the environment

  • Be proactive about prevention.

    Once a flea infestation has been eradicated from your pet and its environment, you should continue to treat all your pets regularly as this can considerably reduce the chance of flea re-infestations. Being proactive about prevention is important with any health condition. As fleas can be found all year round and can multiply rapidly, it is important to treat your pets on a regular basis – usually monthly. You should ask your vet and the practice staff for advice.

  • Did you know 95% of the flea population survives in the environment and not on the pet?

    Fleas are the most common of all external parasites found on pets.  An infestation is both unpleasant and potentially dangerous for pets and their owners. Ctenocephalides felis, the cat flea, is the most prevalent species of flea found on both cats and dogs.

    A flea‘s entire life cycle lasts anywhere from a few weeks to several months.  As fleas thrive in warm environments such as in centrally heated houses, they can survive year around. In warm conditions the lifecycle may be quite short but under the right conditions pupae can last for many months in the environment, only maturing when exposed to the right type of stimuli.

    During the lifecycle fleas go through a complete metamorphosis in three main stages:

    • Adult fleas jump on to a host (e.g. cat, dog or human) and within minutes begin feeding on the host’s blood. The flea bites lead to itching and irritation and may also transmit serious diseases.
    • Within 24 - 48 hours fleas begin laying numerous eggs that quickly fall off the animal into the environment.

    The flea Lifecycle

    In a few days these eggs hatch into flea larvae. These larvae dislike light and immediately crawl deep into carpets and cracks in floors making them hard to spot. The larvae spin cocoons in which they develop into pupae and when conditions are right they emerge as new adult fleas ready to jump onto a warm-blooded host and perpetuate the cycle.

  • Q:     I treated my dog for fleas with a spot-on preparation 2 weeks ago and I have found fleas on him again. Is the treatment not working?

    A:     Have you treated his environment as well? If not, eggs are probably continuing to hatch in cracks between floorboards or skirting edges, from within the carpet or in his bedding, and then these new adults are jumping onto him. Once they start feeding they will be killed by the preparation you have applied to the pet.  However a flea infestation can be resolved more quickly by vacuuming the house and using a product which treats residual eggs and larvae in the environment. Your veterinary practice will be able to help you with this.

    Q:     I have found small red sores on my legs and waist which are very itchy. My pet has fleas and someone has told me that the spots could be caused by flea bites. Is this true?

    A:     Yes. Fleas from dogs and cats can bite humans and could cause small sores such as you describe. If you are concerned you should seek medical advice

    Q:     When I apply my spot-on product to my dog I only have to put it at the base of his skull. Does it really kill fleas that I have found near the base of his tail?

    A:     Yes. The spot-on contains a spreading agent that will ensure its effects reach the rest of the dog’s body.