Where do fleas come from? The pests pose problems for both pets and families
Is your dog or cat itching themselves more often? It could be a sign of fleas - even when it's cold outside.
Dr. Aly Cohen, a veterinarian at Cornell University's Riney Canine Health Center, urged pet owners to stay vigilant year-round as fleas can infest all types of animals and households
Experts told USA TODAY that pet owners must stay vigilant year-round by regularly checking pets and cleaning their homes of fleas. People often let their guard down in the cold months, which scientists say can be troublesome as fleas have different life stages.
"The most common places we think of are in warm and humid places with brush piles or damp, shaded and warm areas," said Dr. Aly Cohen, a veterinarian at Cornell University's Riney Canine Health Center. "Under a deck with leaf debris, that creates this perfect humid warm area. Year round, those environments are actually inside the home."
Where do fleas come from?
Simply put, Cohen said fleas are a regular occurrence in the environment. Associate Professor of Entomology at the University of Kentucky Jonathan Larson added if fleas aren't coming from a kennel, groomer or another home, they're from wild animals on property.
"Possums and raccoons are more likely to drop fleas in the area," he said. "They can be the raft that gets them around town."
Both said fleas are not a diagnosis of a household's cleanliness but of sheer bad luck.
The pests live in four life stages: egg, larva, pupa and adult fleas, according to the Centers for Disease Control and Prevention. Adults are commonly found on pets and feast on their blood for survival. Fleas typically live longer, Cohen said, as people focus on what they find on their pets but not the home.
"Treating the environment is the most difficult part to treat as you have to wait for the egg to hatch," she said.
Can fleas live on humans?
Some can. Humans have their own species of fleas, Cohen said, but they can't live long off of people. She said a main determinant if you have fleas are long itchy red bites on the skin. The reaction could be stronger for those with sensitive skin or allergies.
The pests become more of a problem when they attach to pets. That prompts a long, arduous treatment process, Cohen and Larson said.
How to get rid of fleas?
Both recommended taking a multi-prong approach to killing fleas. Fleas must be killed off the pets, the pets' common areas and the home for up to a year after infection.
On pets, Cohen said flea baths are OK, but not to be used alone as it's only good for the day and kills the adult fleas. The best option, for animals, is a medicated treatment prescribed by a veterinarian.
"There are other options beside baths, if you diagnose and do a bath first, that's fine and then go to a topical," she said. "Otherwise, you can go right to applying the medicine. Some will kill them in 6 hours or 24 hours."
Larson said killing other life stages takes take and dedication. He recommended vacuuming often to suck up larvae, cocoons and eggs in the carpet. Cohen added if fleas are in the cocoon stage, vacuuming will force them to wake up, making it easier to kill.
"You use a prescribed medication from your vet, then get to an area they hang out in the house," Larson added. "If it's a kennel, bed or chair, you have to get them there. Fleas will eject their eggs, and will feast on dried blood."
Do fleas die in the winter?
No. Cohen encouraged people to continue flea and tick preventatives when it is cold outside. If an animal previously had fleas, owners should keep watch of the pests as they nest into carpet fibers and can live up to a year dormant as eggs.
She warned people to not avoid the treatments as they kill
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This article originally appeared on USA TODAY: Where do fleas come from? Quick guide on what to know about the pests
