However, data averaged from several homes and pets using geometric means to evaluate product efficacy can occasionally mask
potential outliers. Understanding the limitations of study data analysis is important because while most products with residual
activity work well most of the time, problems with perceptions of flea control failure occur. In a typical scenario, a pet
is treated appropriately and flea numbers initially decrease but then rebound three or four weeks after initial treatment.
Data from one home clearly illustrate such a problem (see related sidebar titled "Focus on residual activity: Case study data reveal a clearer flea control picture" ).
As good as the modern veterinarian-recommended flea control products are, direct environmental control may still be needed
with severe flea infestations because the pet owner may not want to wait three to eight weeks until the problem is resolved.
Measures to reduce the premises infestation include washing pet bedding, vacuuming carpets, washing area rugs, using flea
light traps, and applying insecticides to the indoor and outdoor areas. These insecticides might include pump sprays, directed
aerosols, total release aerosols (commonly referred to as bombs), or the services of a professional pest management specialist.
Goal # 3 Prevent new infestations with lifelong flea control
Now that the infestation is eradicated, pet owners should continue to treat their pets. Remind owners that numerous animals,
such as feral dogs and cats and wildlife, move through the neighborhood and yards carrying fleas. These flea-infested animals
are continually depositing flea eggs in the outdoor environment, which can start the problem all over again. So keep pets
on lifelong flea control either seasonally (e.g. summer and fall) or year-round. Then when fleas that have developed from the eggs deposited by feral dogs or cats or wildlife
jump onto a treated pet, the fleas will either be killed or their eggs destroyed. Thus, future flea infestations of beloved
family members will be prevented.
Effective flea control starts with effective client communication. Clients need to be educated on the objectives of a flea
control program, taught how to properly administer a product, and given a detailed explanation of what to expect once a flea
product is administered and the pet is back in the infested premises. If we set realistic client expectations through education,
we can meet them, but if we allow clients to set their own expectations, we will rarely be successful.
Editors' note: Dr. Dryden is a consultant and speaker for Pfizer Animal Health, Novartis Animal Health, Bayer Animal Health, Merial, and
Michael W. Dryden, DVM, MS, PhD
Department of Diagnostic Medicine and Pathobiology
College of Veterinary Medicine
Kansas State University
Manhattan, KS 66506
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