By Nancy C. Hinkle
and Dan Rahn
University of Georgia
And cat fleas aren't just for cats. These common fleas get their blood meals from people, too, and many other mammals -- dogs, raccoons, skunks, even birds. Getting room and board on so many hosts makes them tenacious pests of both pets and their homes.
Their feeding isn't fun for the hosts. Cat fleas' bites itch, and pets scratch and bite themselves repeatedly. Puppies and kittens with lots of fleas can get anemic and even die.
Cat fleas don't carry many diseases. But they can transmit the agents that cause typhus and cat scratch disease. They're intermediate hosts for dog tapeworms, too, which can affect small children as well as dogs and cats.
Flea allergy dermatitisMany dogs and some cats develop flea allergy dermatitis. For them, the bites trigger a cascade of symptoms in a misery of excessive grooming, hair loss and bare skin with weeping sores that often lead to secondary infections. And the best way to treat it is to get rid of the fleas.
Cat fleas are small, dark, reddish brown, wingless insects with bodies that are flattened side-to-side. They're covered with backward-pointing spines that make them hard to pull from a pet's coat. And their long hind legs are well adapted for jumping.
Female fleas mate and start laying eggs within two days. Averaging one an hour, they can lay hundreds of eggs in the several weeks they live. And when conditions are right, it takes only a couple of weeks for the eggs to become adults.
Only adults biteThe only good news is that only adult fleas are parasitic. All other life stages develop off the host.
The eggs, about a millimeter long, hatch in two days, or one with ideal temperatures. The white, eyeless, legless larvae seldom travel far, feeding on flea feces, dry blood and other things that collect where pets live. The larvae develop in 10 days to a month, then spin silk cocoons that look like little dirt clods or lint balls.
In the cocoons, the larvae change into pupae and then adults in about four days. And when the time is right -- from less than a day to more than a year -- the adult breaks out in its life-or-death search for a host.
Since they have to have blood to survive, treating host animals is the best way to kill fleas.
Flea bustersSeveral products do this well. Many contain pyrethrins, which are safe and effective but don't provide residual control. Other over-the-counter compounds include spot-on permethrin products, which are limited to dogs and can be lethal to cats.
Veterinarians can prescribe products that give weeks of control with one application. These are applied in small amounts on the back of the pet's neck and spread over its body in skin oils.
Other products come as sprays. These kill fleas on the pet within a few hours and then keep working for weeks.
Once pets have been treated, it will take a while for the fleas around them to die off. As they develop, fleas keep hopping onto the pet, which keeps "harvesting" them from surrounding areas until they've been killed.
Insect growth regulators can break the flea life cycle. These compounds don't kill adult fleas. But they do prevent eggs and larvae from completing their development. So any fleas brought into the area won't build up a sustaining population.
Places where pets hang out gather flea eggs and larval food. So keep these areas clean and vacuumed, and treat them to prevent infestations and protect pets and people.
(Dan Rahn is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)
(Nancy Hinkle is a Cooperative Extension entomologist with the University of Georgia College of Agricultural and Environmental Sciences.)