Everyone with pets at one time or another gets exposed to the aggravation of fleas. I found the following YouTube video, How to get rid of fleas
I also came across this post, Into the Garden: Prevent fleas in the yard naturally that claims, One preventative measure that keeps coming up from several sources is the use of diatomaceous earth. Made from the finely ground fossils of prehistoric freshwater diatoms, it kills common household and garden pests like roaches, ants, fleas, beetles, silverfish, slugs and other crawling insects within 48 hours of contact. A long-lasting control, it’s sprinkled into cracks and crevices where bugs hide. Insects cannot develop resistance, as there is no buildup of chemical immunity.
According to Yahoo.com, the fine powder absorbs lipids from the waxy outer layer of insects’ exoskeletons, causing them to dehydrate.
Diatomaceous earth can be found at Green’s Feed and Seed, Lowe’s, Home Depot and other garden stores. It runs $10 to $12 for a couple of pounds. For dry application, use a duster and cover the entire plant, and apply to both top and bottom of leaf. For young plants, as little as 2 pounds per acre may be adequate. For larger plants, 5 pounds per acre is probably sufficient. DE will need reapplication after a rain. It applies best when there is dew or after a light rain.
I found even more at eHow, Natural Way to Get Rid of Fleas on Animals, I am sure one or all of these remedies will prevent and cure ailments with fleas.