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Fleas: The invasion has begun

Fleas: The invasion has begun

Abby cat had a flea infestation that gave her dandruff and matted fur. As a result, she got a bit of a buzz cut.


Posted on June 11, 2011 at 1:21 PM

Just in time to compete with summer blockbusters about alien invasion and talking robots, our pets have opened the door to an all too familiar invader – the common flea.  Unfortunately many households with pets will experience this pest this summer, and see first-hand the damage it can cause.  With a little knowledge and prevention, however, we can make this an itch-free summer for all.

The itch is the tip of the iceberg

We’re all aware of what a flea can do to our pets – the sometimes non-stop itching and scratching are certainly one of the signs we are most used to seeing.  But most of us are unaware of the other problems these pesky insects can cause – some of which are much more serious:

• Flea Bite allergy: While most dogs and cats are allergic to flea bites to some degree, some are MUCH more sensitive than others (think of this like the allergies some people have to mosquitoes or bee stings).  A single bite from a single flea can make some dogs and cats so itchy they will actually chew out a majority of their hair, and scratch large wounds, requiring medical attention.  What’s worse is that this itch/scratch reaction can last for up to 2 weeks after the flea bit the pet! 
• Flea Anemia: Let’s not forget why fleas like our pets so much – they are the fleas’ source of warmth, shelter, and FOOD.  Dog and cat blood is food of choice for the fleas we usually see (although human blood will do if dog or cat is not available...).  While one flea can hardly eat enough to make a difference, THOUSANDS of fleas can easily debilitate their host by heavy feeding.  Young animals (puppies, kittens) and very old or ill animals are especially at risk because they are not able to groom away fleas as effectively as their adult/healthy counterparts.  It is not uncommon to see an entire little of kittens succumb to these blood-thirsty parasites.

• As if this was not bad enough, fleas are also VECTORS for other diseases and parasites.  Flea larva eat tapeworm eggs and then pass the infection on to our pets.  While not an immediate health risk, these worms are certainly unsightly.  On a more serious level, Feline Infectious Anemia is caused by an organism transmitted by fleas.  This infection can be fatal to cats.  Plague (which wiped out a significant portion of the population of Europe in the middle ages) and Bartonellosis (“Cat Scratch Disease”) are also transmitted through flea bites AND can infect humans (here’s a link to a story out of Oregon earlier this month

So which pets are really at risk?

It seems that everyone KNOWS about fleas, but in spite of television commercials, newspaper articles, and conversations with veterinary professionals, many are in denial that fleas could be a problem for their pet.  Until proven otherwise, however, I assume that ANY pet is susceptible to flea infestation.
It is commonly believed that the indoor-only pet (usually a cat) is safe from fleas – without exposure to other animals in the environment, it is reasonable to assume that there is no way for these pets become exposed.  Unfortunately, several factors will often lead to these isolated pets becoming infected:

• Other household pets that go outside.  Even if treated, these pets can transfer fleas into the home – where they are more than happy to dine on the unprotected pet.  I have seen cats living in 10th-story condos with flea infestations that rival their indoor-outdoor counterparts. 
• Some “indoor only” animals are allowed to spend time on an enclosed patio or balcony.  Unfortunately this gives fleas all the opportunity they need to “move in” and start reproducing.
• Fleas can be transferred indoors on people.
• In condo/apartment settings it is possible that a neighbor’s indoor/outdoor pet is bringing fleas into a common hallway, where they can make it into your home and onto your pet.
Unfortunately most of the time these pests go unnoticed by pet owners – unless a pet is excessively scratching and chewing at itself, fleas do not announce their presence. Only when their numbers are sufficiently elevated (an “outbreak”) do we begin to see them on our pets (or worse) on us.  A simple check most pet owners can do takes no special equipment, and costs nothing.  Allow your pet to stand above a white cloth or paper towel.  Rub their fur back and forth over the towel, allowing any dirt and debris to fall onto it.  Flea “dirt” (essentially flea feces) looks like coffee grounds, and will turn red when wet (sprinkle some tap water onto it).  An inexpensive “flea comb” can  also be purchased at any pet store.

What can be done?

In the past, much has been unsuccessfully attempted to prevent flea infestations – from food additives like garlic and yeast, to toxic insecticides used on the pet or in the home.  Not much showed long-term effectiveness, and concerns grew with the increasing use of toxins and insecticide resistance.  Fortunately with some planning, and some help from newer, safer flea preventatives, we can protect our pets and our homes from fleas all year:

1) Discuss an appropriate parasite prevention plan (fleas, ticks, and intestinal parasites) with your veterinarian BEFORE there is a problem.  You will save your pet the agony, and protect them (and yourself) from the diseases associated with fleas.   
2) Use products that attack the flea lifecycle at multiple stages – many products now have ingredients that kill adult fleas AND prevent juvenile stages from reaching maturity.  Focusing on multiple aspects of the flea’s biology results in greater control and decreases the likelihood they will develop resistance to a single agent.
3) Avoid “over the counter” products (drops, collars, bombs), as many still contain the dangerous insecticides which can be harmful (or even fatal) to pets. 
4) Treat all year.  All too often people wait until they see a flea – at which point their environment (home) is loaded with eggs, larva, and pupae.  The advantage at this point is in the flea’s court, and it may take months to get the problem under control.  Remember that while OUTSIDE may be inhospitable to fleas in the cooler months, many dogs and cats can still be exposed at the groomer, boarding kennel, daycare, or common areas of multiple family dwellings.
5) Actively look for signs of infestation – don’t wait for the fleas to find you! 

Dr. Cary Waterhouse is owner of Lake Union Veterinary Clinic. He has been practicing exclusively in cat and dog veterinary medicine in the Seattle area since 2002.

Dr. W will be on New Day Northwest on Thursday to talk about fleas, heat and summer travel. Watch at 11 a.m. on KING 5.