Fleas without pets — where did they come from?


It’s possible to have fleas without pets, especially when a home or apartment was previously infested. Example: The past occupant moves out while larvae are developing in the carpets. The fleas reach adulthood and go dormant when they can’t detect a host. A new tenant moves in and the fleas emerge to find a blood meal. With no cat or dog, fleas should go away on their own. Vacuuming will speed up the process.

Make sure the pests you are dealing with are fleas. If they are bed bugs, a more intensive pest control regime is required. What do fleas look like?


Where the Fleas Came From

Dormant Pre-Emerged Adults

After pupating, adult fleas go dormant inside their cocoons. The fleas remain there until they detect heat and physical pressure, which indicate a nearby host. The quiescent (dormant) state can last as long as five months. However, once stimulated, the pre-emerged fleas exit their cocoons in five seconds.

Fleas can occur without pets when moving into a home which was previously infested with fleas. When the previous occupants moved out, immature fleas were developing in the carpets. The fleas reached adulthood and became quiescent in the absence of a host. New residents moved in, walked on the carpets and triggered the fleas to emerge. In these instances, fleas are abnormally aggressive. They will attack and feed quickly, as they have been without a host and food for an extended period of time.

A similar situation can occur when wildlife enters into a house, making it their temporary habitat. The animals (e.g. raccoons, opossums or feral cats) typically enter in through basements, attics or crawl spaces. When they eventually leave, immature fleas will be developing in the home. The cocooned adult stage is reached, and they then wait for a host.

Hitch-hiking on Clothes

It’s possible for outdoor fleas to jump and attach onto a person’s clothes. The insects then hitchhike into homes. However, this rarely occurs.

How to Eliminate the Fleas

Fleas Can’t Survive on Humans

Fleas will go away on their own in the absence of a primary host. Fleas occasionally bite people, but man isn’t a preferred host. They can’t produce enough eggs on human blood to keep the infestation going. Plus, cat fleas won’t breed or lay eggs on people. Instead, they take a blood meal and then leave. Additionally, fleas are adapted for furry hosts. It’s difficult for them to jump and attach to hairless human skin. If they do successfully attach, the fleas are easy to see and kill.

It’s possible to prevent flea bites while waiting for the infestation to end. Wear long pants and tuck the legs into socks. Fleas can’t jump much higher than the ankles, and rarely bite higher than the lower legs (unless the person is sitting on the ground).

Vacuum Regularly

Flea pupae and pre-emerged adults are fairly resistant to insecticidal carpet treatments. They reside at the base of carpeting where sprays can’t penetrate.

The best way to eliminate the dormant fleas is to regularly vacuum carpets. Vacuuming creates heat and pressure, the exact stimuli which trigger emergence. The adult fleas quickly leave their cocoons and move to the carpet canopy where the vacuum cleaner sucks them up and kills them.


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  • Utkan April 2, 2016, 8:02 pm

    I think the “However, this is a rarely occurs.” part has some sort of a grammatical error.