You & Your Pet by Dr. Wise

Rhode Island Veterinary Medical Association 11 South Angell Street #347 · Providence, RI 02906 (877) 521-0103 (866) 277-0238 Toll-Free ·Fax

As much as I like to see the weather warm up, it makes me shudder to think that it is flea season again. As a professional pet rescuer, and the owner of four dogs and six cats, it is a nightmare each spring to try to wade through all the information on flea products, on what will work best and is the best value for my money. Can you give me advice to help once and for all?

I believe that to best counsel clients on flea control, it is important for them to understand the life cycle of a flea. The adult flea that you see on your pet is only one to five percent of all the fleas found in your pet’s environment. The majority are in the egg, larvae, and pupae form and are very hard to detect with the naked eye. The adult flea hatches out of the pupae and hops onto the host and spends the rest of its short two-week life on the pet. The other three stages are in your carpet, beds, couches and yard, after the ground warms in the spring.

The pupae stage is the most difficult to treat as it is very resistant to most chemicals, and can stay in this latent state for an extended period of up to a year, while waiting for the proper conditions to hatch. The most effective flea prevention is in place before the season starts, that is by April or May. The treatment also needs to attack the egg and larvae stages, which accounts for over 80% of your flea population.

Products that treat these stages are often termed "IGR" or insect growth regulators. When these products are fed to your pet or placed on their skin, they are ingested by the biting flea (which gets a blood meal within 30 seconds of jumping on the animal). The chemicals in these IGR’s affect the "chiting" in a flea, which is their external skeleton. This is a substance that neither man nor animal has and this makes this chemical extremely safe for us!

Within a 30-day period, if there are fleas present in the environment, these products should have removed 98% of the population. In a household with dogs and indoor only cats, it is important to have prevention on everyone, as we even carry fleas to our pets on our bodies. When they find out what they jumped on though, they are quick to get off and find the right kind of creature! The old insecticide flea collars that only killed adults were never effective, but there are wonderful IGR collars out now, that work extremely well and are a low cost way to treat those indoor cats.

If time slips away from you and you find your house in the middle of a flea infestation in July, be assured that there are some new safe alternatives that kill adult fleas only by attacking their nervous system and that leave the pets’ body quickly with no residual action. After you have treated the environment also, you can quickly put your preventative into place. One last note: Cats are extremely sensitive to many types of insecticides sold over the counter. Read the label carefully or just wait and call your veterinarian for the best treatment recommendations. You will save lots of money in the long run! Enjoy your summer with your pets!

We have three dogs and a cat who spend most of the time in the house, but are outdoors some of the time, especially when the weather is nice.  One of the dogs recently developed a rash on the top of her tail, near her rump.  She has chewed the area until the skin is infected and the hair is thin.  The veterinarian said she has flea bite allergy.   We saw only two fleas.  The other animals seem to be fine, no fleas or skin problems.  What causes the allergy and why aren't the other pets affected?   Also, how do we get rid of a flea problem?

Flea bite allergy is fairly common in both dogs and cats.    Not all animals are allergic to flea bites, but the problem can be severe in pets that are allergic.  When a flea bites an animal, it injects saliva to prevent the blood from clotting at the feeding site.  The allergy is due to sensitivity to this saliva and causes an itchy rash.  The affected area might be quite large and may become infected, especially if the animal scratches or chews at it.  Areas typically affected include the tail base, back of the rear legs and sometimes the belly.  A single flea bite may be sufficient to trigger a reaction in allergic patients.

Sometimes few, if any, fleas are actually seen on the animal.   We usually identify the allergy by observing fleas, flea dirt (excrement), eggs and the like along with the skin reaction.  The diagnosis can be confirmed with a skin or blood test.  If one animal in a household with multiple pets has fleas and comes into the house, it is safe to assume that all the pets have fleas. 

Fortunately, there are several excellent products available for treatment and prevention of fleas for both pets and the house.  Your veterinarian can help you work out a plan that suits your needs.  For your allergic dog, topical products are available that are extremely effective for treatment and prevention.   They are safe for pets and people, especially compared to products used in the past.  Fleas thrive in warm, humid environments, so late summer is typically the peak of flea season.  But it is never too late to start a treatment/prevention program and avoid the irritation and discomfort these parasites can cause you and your pets.