Fleas don’t stay on humans. They’ll leave after obtaining a blood meal. Fleas may hide in clothing if they’re disturbed while feeding. In rare instances, if unable to find a way off the person, a flea may remain there for 1-2 days and periodically feed. Generally, people make poor hosts because of our lack of body hair.
When Fleas Bite People
Cat fleas can feed on a variety of mammals. However, they do have preferred hosts and humans aren’t one of them. Still, a person living in the same environment as an infested pet may get bit. Fleas emerging from cocoons will jump to the nearest potential warm-bodied host. When pets are absent, this may be a person.
Humans are Poor Hosts
Humans are suitable hosts for cat fleas. In natural settings, fleas can’t survive or lay eggs on a diet of human blood. To do so, they’d need to feed freely for days, which doesn’t happen on humans. Even if they could feed enough, fertility is greatly reduced on human blood.
Fleas co-evolved along with their primary hosts. Cat fleas are specially adapted for living in the dense fur of small animals. For instance, their bodies have numerous bristles which prevent them from being easily removed from hair.
Flea survival is primarily governed by their ability to remain on a host. Fleas can’t attach easily to humans because of our absence of body hair. They have a difficult time even jumping onto people. And, upon reaching human skin, they’re clearly visible due to the lack of hair. Thus, they’re quickly picked off, often before they can feed.
Fleas Leave Humans after Feeding
Fleas leave immediately after taking a blood meal from a person. They don’t breed on humans. They’ll typically bite 2-3 times before leaving. The average blood meal duration is 7.4 minutes for females and 4.4 minutes for males.
Fleas can’t bite through clothing. They prefer feeding in covered areas, and will move underneath clothes to bite exposed skin. Sometimes, if they’re disturbed while feeding, fleas will hide in clothes for short periods of time. If a flea can’t find a way to leave, it may remain there for a couple days and periodically feed.
Fleas Stay on Cats and Dogs
Fleas will permanently stay on dogs and cats after jumping on them. They feed, mate, and lay eggs directly on their primary host.