HOME IMPROVEMENT : The Truth Shall Set You Flea: All the Facts on a Common Parasite

Like a bandit in the Badlands, the flea uses your carpet and furniture as hide-outs from which to stage raids on unsuspecting passers-by. Ctenocephalides felis of the order Siphonaptera is an ambush artist with an appetite.

Nick Nisson, an entomologist for the Orange County Agricultural Center in Anaheim, says there are about 2,400 flea species spread across the globe. Of those, 325 reside in North America. There are rat fleas, bat fleas, bird fleas, even human fleas (Pulex irritans).

But in an urban area such as Orange County, there are mostly cat fleas, says Nisson. Lots of cat fleas.

As might be expected, cat fleas like to hang out on cats. But a hungry cat flea will forage on any number of available mammals, including dogs, foxes and opossums.

Cat fleas are often mistaken for other flea species. Some people in Huntington Beach (the beach city is a hot spot for flea infestation, according to pest control experts), think their homes and pets are crawling with sand fleas (Tunga penetrans), whereas the parasites in question are actually cat fleas.

Ernst Bruckmann, an 18th-Century physician, once theorized that fleas lived on the moon. He went so far as to claim that lunar fleas grew as big as elephants. Needless to say, Ernst was misinformed.

Fleas are decidedly earthbound creatures of more modest dimensions. Although some flea species--such as the mountain beaver flea--can grow a quarter-inch long, most fall in the 1- to 3-millimeter range.

Here are a few more flea facts to ponder:

* Strictly speaking, fleas do not sting. They sink a barbed stylet into the skin through which they suck their victim’s blood. About 20 flea species regularly dine on humans, although it is claimed that human blood makes most fleas nauseated. A hungry flea is seldom a picky flea, though.

* Externally, fleas are flat for easy movement through fur, feathers and hair. A tough insect, they are covered by armor-like spines. Some species are swept-backed, some hunchbacked, while others appear to have curved spines. All are studded with rows of tough bristles. The bristles act like insect Velcro to help fleas cling to their unwilling hosts--understandable in light of all the scratching, biting and shaking going on.

* Fleas are highly adaptable. They have learned to thrive in desert and snow--and just about every climate in between. They can survive frozen for up to a year. A quick thaw will bring the “fleasickles” around again, defrosted and refreshed.

* Fleas, as a species, are old. Fossil fleas 200 million years old have been discovered in Australia.

* Some species of fleas can easily leap 150 times their own length or the equivalent of a man jumping to the 80th floor of the Empire State Building. Fleas routinely pull 140 g ‘s during blastoff, somersaulting into the air, tumbling wildly, legs extended, hoping to latch onto any passing meal.

Not all fleas jump, however. Some, such as Asian livestock fleas, which live full-time on their hosts, need not chase after meals and so have lost much of their leaping ability.

The flea times its jumps to vibrations in its surroundings (although it can also hone in on heat, air currents and exhaled carbon dioxide). When its built-in seismograph detects what might be an edible tremor, powerful leg and thorax muscles catapult the bug upward. If the trajectory is right and the target digestible, then dinner is served.

* When it comes to strength and stamina, fleas are Herculean. Scientists testing one robust rat flea once counted 30,000 nonstop jumps.

* The tiny creatures are carriers of plague picked up from the blood of infected rodents. Three great pandemics of flea-spread plague have killed more than 200 million people. Although Orange County is not zoned for plague, outbreaks have occurred here in the wild rodent population, the latest in 1984 when the disease was found in both ground squirrels and their fleas in the Anaheim Hills.

Fred Beams, an official with the county’s vector control district, says Orange County has been plague-free since the Anaheim Hills contagion was ended. Both squirrels and wood rats from around the county are routinely tested for signs of plague. Some flea species--such as the Oriental rat flea, the classic carrier of bubonic plague--are also tested, but not the omnipresent cat flea, which Beams calls an unlikely source of human disease.

* Fleas are with us year-round in Orange County, but in the spring and summer months the true invasion starts. Although each flea season seems worse than the last, entomologist Nisson claims that flea populations hold fairly steady from year to year.

And every year, no matter how relentlessly we bomb our homes with complex molecular compounds, spray our pets and yards, or vacuum our carpets, we are fighting little more than a holding action against the invading parasites. We cannot win the war, say entomologists, though we can massacre the enemy by the millions.

The war against the flea has produced a chemical arms glut, of sorts. An array of anti-flea potions is available, especially for the family dog and cat. There are flea sprays, powders, dips, shampoos and collars.

Tests conducted by the U.S. Department of Agriculture show that a nontoxic mixture of citrus oil and water will kill fleas when sprayed on a cat. Run orange or grapefruit skins through a blender then simmer them in a pot of water. Sponge the pulp and liquid into your pet’s fur.

If you place a pan of water on the carpet, put a light over it and leave it overnight, fleas in the darkened house will hop toward the light source without suspecting the watery end that awaits them. (Fleas do not swim, but they can use the surface tension of water like a liquid trampoline to bounce themselves to safety. Adding a little detergent to the water lowers its surface tension.)

Daily vacuuming of the entire house, including the furniture, will suck up not only fleas, but their eggs and larvae as well. Spiking the sweeper bag with flea powder or an insecticide will finish the job.

When the fleas get tough, it may be time to call in a professional, like Fleabusters, a Southern California company that guarantees its in-home treatment as not only deadly for fleas, but safe for the environment, your pets and you. Fleabusters’ representative Gary Thorn says his company uses a blend of inorganic salts to dehydrate fleas to death. Treated carpets and furniture will continue to kill fleas for up to one year, Thorn claims. The cost to treat a two-bedroom house is $160.