Flea Season : No Way to Get Jump on the Pests, Experts Agree

Times Staff Writer

When Moise Mizrahi, who is in charge of pest control for San Diego County, walked into a vacant apartment once to check for roaches, he looked down at the white tennis shoes worn by the manager of the complex.

“There were so many fleas, her shoes looked like spotted tennis shoes,” he said.

The apartment had been empty only a few weeks, but the previous tenants owned a pet. In that short time, the fleas had multiplied so much there were “hundreds,” Mizrahi said.

As spring unfolds and summertime follows, the promise of similar flea problems hangs heavy over San Diego County. The microscopic enemy to a man’s best friend will once again prove to be a huge headache to humans as well.


Narrowly defined in the dictionary, the flea is a “Siphonaptera . . . a small flattened, wingless insect with large legs adapted for jumping. As adults they are bloodsucking parasites on mammals and birds.”

Fleas thrive in the spring and early summer months, when the temperature ranges from 65 to 80 degrees and humidity hovers at 70%--the normal weather conditions for San Diego, Mizrahi said.

“You bet it’s a real problem in San Diego. There is no cold to kill them so they breed year round,” said Dr. J.B. Goetze, of Animal General Hospital in La Jolla.

According to David Faulkner, entomologist at the San Diego Natural History Museum, fleas have been around for 50 million years.


Longevity is not the flea’s only strong suit. It can jump several feet into the air.

“I’ve heard that if a human being could jump as high, relatively speaking, as a flea, he could theoretically jump over the Empire State building,” Goetze said.

Because of that, beating the flea population--or at least coping with it--has driven some people to desperate tactics.

There is the case of Pam Clark, administrative assistant in the humanities department at UC San Diego. She owned a long-hair cat while living in Los Angeles a few years ago. She went to bed with flea collars on both her ankles.


Clark still has three cats. During the summer, she has to vacuum the rug every day and comb her cats’ hair with a close-tined comb several times a week to guard against fleas.

Exterminators say there are even instances where fleas, nesting on cats that live on rooftops, jump off their hosts and infiltrate buildings through the ventilation systems.

Experts agree that there is no easy way to rid your home of fleas. Today’s fleas are rapidly becoming resistant to the chemicals traditionally used to control them. “Chemicals that worked 10 years ago don’t even slow them down now,” Goetze said.

And all it takes for a new outbreak is one pregnant flea.


That flea can lay hundreds of eggs, which could mature into a batch of full-grown adults fleas--ranging from one-sixteenth to one-fourth of an inch in length--in a matter of weeks. The life cycle of a flea can be anywhere from a few weeks to a couple of years.

They can live without food for a year. “They will feed on any organic debris, like cat skin or hair,” Mizrahi said.

But when they are really hungry, they will go looking for their favorite dish: blood.

A flea drinks the blood of an animal by puncturing a cat or human’s skin and injecting saliva through a built-in siphon. The saliva contains an anti-coagulant that makes the blood flow smoothly so the flea can drink its fill, Faulkner said.


There are hundreds of species of fleas, according to experts. There are sand fleas, cat fleas, dog fleas, rat fleas, mouse fleas and squirrel fleas, named for their hosts. But the most common fleas found in the San Diego County area are dog and cat fleas, Mizrahi said.

Because humans have comparatively little body hair, humans are not their favorite hosts, Faulkner said.

But fleas can be brought into the home to lurk in the living room rug by riding on a pants leg or shoe, Goetze said.

While fleas found on dogs and cats tend to bite humans below the knee (a short jump from the animal’s back to the nearest patch of human skin), the so-called human flea is found in bedding and attacks a person’s trunk area, Mizrahi said.


Human fleas are uncommon in the United States, he added. Disease transmitted by fleas is also unusual, Mizrahi said.

So how do you get rid of fleas?

Vacuuming is good, Mizrahi said, but you must empty the vacuum cleaner immediately, because the fleas will continue the reproductive cycle in the dark of the vacuum cleaner bag.

Moving East may be the ultimate answer. Fleas can’t tolerate colder climates.


Otherwise all one can do is groom pets regularly and have the premises sprayed for pests.