All About Fleas – Part 1 of 2

Ahhh, summer!  What’s better than a Western Washington summer, with our warm days and still enough moisture to keep our beautiful, lush greenery?  We all love it, and so do our pets, but unfortunately, we have some unwelcome guests that love it too… Fleas!

Fleas thrive in warm, moist weather.  Since we have such a perfect environment for fleas, it’s hard to completely avoid them, but in this two-part series, for our July and August blog posts, we’ll give you a little background information to aid in recognition, prevention and treatment:

If you are lucky enough to have never had a pet with fleas before, let’s start with a description of what to look for…

Identifying a Flea Problem

Fleas are a brown to reddish-brown parasite that can easily be seen without magnification.  Since they are about 3 mm long, you would think the diagnosis should be easy, but frequently, finding fleas is not as simple as it sounds.

We all know that scratching can be a sign of fleas, but what else should we be looking for?  One of our most common ways of diagnosing fleas is to do a flea combing. We use a very fine tooth comb, especially designed to trap “flea dirt” and sometimes even adult fleas.  The most likely place to find “flea dirt” or fleas is the dorsolumbar area: on top of the back of the dog or cat, near their rump, basically from the mid-back to the tail.

The term “flea dirt” is a euphemism for flea feces. It is a dark reddish-brown to black material that looks like specks of dirt, but can often be seen to have a long, slightly curved shape, like a comma.

To distinguish flea dirt from garden dirt, just place it on a white tissue with a drop of water and gently rub it.  If a faint rust color appears on the tissue, you’ll know it is the digested blood of flea dirt.

Sometimes we don’t have the luxury of seeing fleas or “flea dirt.”  Other signs of fleas may include:

• Dorsolumbar alopecia (hair loss on the rump)
• Scratching or biting at the skin with the front teeth
• Red or crusting skin
• Greasy fur
• “Hot spots”
• Twitching or chewing when being pet or scratched

Because our feline friends are such fastidious groomers, they can make it even tougher to find fleas. Sometimes we don’t have obvious signs of fleas, but need to rule it out.  If your pet has signs of skin disease or pruritis (itching), but we don’t find any fleas or “flea dirt,” you may still be asked to do a trial of flea control to see if it alleviates signs.

Given that fleas are so ubiquitous in our area and fairly easy to treat, compared to some of the other skin issues, a flea control trial is usually wise.

Sometimes we see clients that are concerned that we will think they don’t take good care of their pet because they have fleas. Obviously, since you brought your pet in for a visit, you’re a conscientious pet owner!

Never feel bad that your dog or cat has fleas.  We’re here to help you fix it. 

Secondary Problems Due to Fleas

Sometimes a dog or cat can have fleas for just a short time, but develop dramatic skin lesions due to a hypersensitivity called flea allergy dermatitis. This is an allergy to the flea saliva that is injected into the skin at the time of the bite. Animals with this type of hypersensitivity can induce enough self-trauma by scratching, biting and chewing that hair loss and red, bleeding skin can develop in a matter of weeks.

Besides an annoying itch and skin allergies, the stress of chronically itching can also play a role in your pet’s mental well-being.

Another very common problem secondary to fleas, is tapeworms. Dogs and cats will naturally groom fleas off of themselves and become infected with tapeworms from ingesting the fleas.

How can you identify tapeworms? The photo at right shows sesame seeds on the left, tapeworm eggs on the right. You may see these rice-sized, pale yellow or white tapeworm segments at your pet’s back end or in fresh stool, They may also be seen on the fecal intestinal parasite screen.

A less common secondary problem is anemia. Anemia can either be due to blood loss from heavy or chronic flea infestations, or from a bacteria that is spread by fleas, which attacks the red blood cells.

Also, although rare, the bacteria (Yersinea pestis) that caused the Bubonic Plague is still transmitted by fleas!

Winter Weather Doesn’t Always Kill Fleas

Surprisingly, one of our trickiest times of years for fleas is winter. As the warm weather wanes, we tend to let down our guard. Fleas, however, are hardy little buggers and they can survive some fairly extreme conditions.

In fact, adult fleas aren’t killed by temperature fluctuations unless held below 20°F for 48 hours or in 120°F of dry heat for several days! 

Plus, many of our pets get fleas from other animals rather than from our outdoor surroundings, resulting in a “flea reservoir” even when the fleas cannot survive outdoors.  For these reasons, we should consider our flea “season” as year-round.

Now that you know what to look for, and a little about some of the secondary conditions associated with fleas, you’ve just about graduated from Fleas 101!  Stay tuned for more in our August blog post, where we will prepare you for battle by discussing treatment.