dchue asked 7 years ago
Hello Adam,
First, thank you for doing so much research and compiling your findings in this awesome site!
I’m wondering if one flea can cause an infestation. I’m currently dealing with fleas. I put on freshly laundered clothes this morning but noticed one flea on my sock right before I left my place. I thought I brushed it off, but can’t be sure if it went into the fabric. What are the odds I would transfer this flea live to my partner’s place later tonight (they have cats)? Would I feel the flea crawling around under my clothes? Would it cling to my clothing somewhere in waiting? If this flea did survive all the way to my partner’s place, could it cause an infestation?
Thank you!
DH
Adam Retzer Staff answered 7 years ago
DH,
The odds are slim that one flea will cause an infestation. It would need to be a female. And before females can lay eggs, they must feed on a host for at least 24 hours. And before they can lay fertile eggs, they need to mate with a male on the host.
Thus, for the flea to be able to start a new infestation, it would need to have come off of an infested host and then somehow got onto your sock. This is highly unlikely. Once adult fleas are on their preferred animal host, they will stay there. It’s extremely rare for them to leave of their own volition. And when fleas are groomed off their host, they are usually severely damaged.
So, that flea that you found on your sock likely just emerged from its cocoon in the environment, and was looking for a suitable host. It hadn’t fed yet or mated. Thus, even if it was a female, it wouldn’t be able to lay viable eggs.
It’s possible for fleas to hide in clothing you are wearing. Usually this happens when they feed on a person and then can’t find a way off. However, they prefer to leave immediately after feeding on humans. I’m not sure if you would feel it crawling around or not. I imagine you would.
Hope this helps!
Adam
dchue
replied 7 years ago You are a godsend! Follow-up question: “they need to mate with a male on the host” does this mean females can’t mate with males anywhere else except for on the host? Not even on the ground?
Adam RetzerThat’s correct. They only mate on the host (perhaps in extremely rare circumstances they may be able to mate off-host).
Neither sex can mate until after they’ve fed on blood for about 24 hours. Feeding dissolves a testicular plug in the males, and triggers ovary maturation in females. So they must be on a host to feed, and once on a host they stay there.
dchue
replied 7 years ago Great to know! According to your articles, a flea in average household conditions cannot survive on human blood. So even if I’m still getting some bites, the adult fleas will eventually die off? Thank you!
That is most likely true. Cat fleas (C. felis) make up nearly all domestic flea infestations. Dog fleas (C. canis) are the second most common. These species can’t survive or reproduce on human blood.
Human fleas (P. irritans) can survive and reproduce on human blood. However, this is a fairly rare species. If you want to ensure you aren’t dealing with human fleas, please see my answer to this question, where I described how to identify species.
dchue
replied 7 years ago Awesome, thank you for your quick response!! One last question… I keep getting some bites on my chest/neck. They look like flea bites, but they don’t itch, or barely itch. When I first got flea bites on my legs, they itched like crazy! Is it common to become “immune” to bites/itching after just a few weeks of exposure? Thank you!!
dchue
replied 7 years ago (p.s. one of your articles describes an itchy “papule” forming 24hrs after the bite, but that doesn’t seem to happen with these bumps)
I don’t think it is possible to become immune to flea bites after such a short exposure time. Immunity in humans is rare, even after years of near constant exposure.
Those skin reactions may not be flea bites, especially because they are so high up on your body. Fleas can only jump to the height of a human ankle, and they bite immediately upon finding exposed skin. Usually bites only occur higher on the body when the person sits or lays on the floor, or on a bed shared by an infested pet.
dchue
replied 7 years ago Thank you again, Adam. I should stop saying “one last question” because there’s always another question!! Is it possible for a person, during the same flea infestation, to have a reaction to some bites and not others? I have a few new bites that itch, with an obvious central red puncture mark, leading me to believe those other papules weren’t bites—unless, I can be reacting to only some of the bites, and not others?
Good question. My first inclination is to say no. All the bites should react the same, as your body’s immune response (sensitization) should be consistent. However, in highly allergic individuals, lesions can arise that aren’t the flea bites themselves but a systemic allergic reaction. This is most common with animals that have FAD (flea allergy dermatis). This isn’t the common immune response though.
J
replied 5 years ago Hello
I don’t see fleas as the people on you tube show. I have caught a few on a flea trap. My legs have a a lot of bites and I didn’t realize it was a flea(s). Now I may get one plus I am wearing long white socks. Does this sound an infestation? I don’t have a pet – maybe it or they came from outside. My daughter doesn’t get bit. I have put down DE and I vacuum. I have sprayed the base boards. I have put a treatment in My yard. What now? I did find one on the floor downstairs maybe it died. There is tile and laminate downstairs.
If you are getting bites on your legs, and you’ve found actual fleas in a trap, then it sounds like an infestation. Adult fleas only account for 1-5% on infestations. So there are likely hundreds more immature stages living in the environment.
The fleas may be coming from outside. Or they may be human fleas (P. irritans) which can live on human blood, but this species is somewhat rare. Another possibility is that mice or rats are in the house, and you are dealing with rodent fleas.
Spraying and insect growth regulator (IGR), pyriproxyfen or methoprene, and vacuuming should end the infestation inside. However, it may not go away if the animal host is not identified and removed (from inside or outside). For example, raccoons can take refuge under porches and cause fleas to develop there.
Nancy Davison
replied 5 years ago Can other dogs get fleas being around a flea infested dog?
Yes.
Charity answered 5 years ago
If i got a kitten from the shelter and notice he had fleas, more eggs than adults but brought the cat back to the shelter and they gave him a bath plus a capstar and when i got back home i gave him flea drops, does this mean my house already has eggs threw the carpet. Im concerned.
ecu
replied 5 years ago If the cat was in your house for any amount of time that allowed the cat to rest or lay somewhere then yes, you probably have fleas in your home. I find it really hard to believe though that a shelter would allow a cat to be adopted before they had resolved a flea problem. As for identifying eggs of a flea, you must have really good eyes because they are sooooo small (about 1/4 the size of an average grain of sand) and are hard to distinguish from dandruff. If you like your cat and end up with fleas – well, welcome to a very large club. Like any other insect, be it ants, spiders, etc… (which few people flip out about) fleas are just another nasty piece of nature that pet owners have to deal with. Get your cat protected so that she doesn’t suffer and then take care of your home. It’s a long road but take a warrior approach and you’ll get there. Your vet should be able to help point you in the right direction. Be very careful to read packaging if going it alone – some flea treatments for dogs are dangerous for cats. READ ALL LABELS CAREFULLY.
ecu answered 5 years ago
This is such BAD information!! 1) Fleas will indeed leave their hosts and it doesn’t take much for that to happen. They only PREFER to stay on their host. In a heavy infestation you can actually see fleas jumping off and on their hosts. Fleas can be carried by wind, shoes and other clothing, laundry baskets taken outside to hang clothes can pick them up in your yard. 2) Telling people that fleas will eventually die off is only right if all your fleas are somehow magically all the same age. As long as you have, fleas, eggs, larva and pupa at various stages – as you will – then you may never get rid of an infestation without intervention – or at all. 3) Adult fleas are not the only stage that bite, so do the larva. 4) Eggs are not sticky and will not stick to a host, they will drop off to somewhere else in your home. 5) Removing fleas with a flea comb will not always damage them. Fleas have very hard bodies (try squishing one… they crunch!) and can withstand a good deal of torture. The hard shell can even prevent some chemicals from entering their bodies. To boot, they have a slight waxy coating which makes it easier for them to slip and slide so they come to rest on one side or the other of that flea comb instead of being impaled or crushed by it. This is why using a flea comb should always be done next to a bucket of soapy water. 6) Not all flea eggs are viable. If the female has not mated, she will produce eggs that will not hatch after her blood meal…. for now. It is strongly believed that fleas are genetically moving towards becoming asexual reproducers – like most other insects. When that happens – look out!
