I have vacuumed 5 times, about to vacuum again, and have sprayed 4 times. This has all been within a week’s time. We have cats but they stay outside. One stray is hanging around that we can’t catch , and one of our cats we can’t catch to put flea treatment on him. We have treated our other two. All this to say I found a hatchling on my white sock earlier today, which I dropped into some water and stuck in the freezer. Would spraying again be a waste of time? I suspect that the fleas we are finding are newly emerged from their coccoon. We also have guinea pigs that we’ve had to move out of my daughter’s room and keeping in a spot off the floor. They are clean thank goodness. I worry about moving them back too soon and them possibly getting fleas. Do cat fleas like guinea pigs as hosts if a cat isn’t available? How long should I wait before I move them back and how long before our torment ends? I hate, hate, hate fleas!
Mamabug,
Sorry to hear about your flea troubles.
Unfortunately, patience is a big part of flea control. It usually takes at least 8 weeks to end an infestation. This is because the bulk of fleas (95-99%) are eggs, larvae, and pupae living in the environment. Many live deep within carpets where sprays can’t penetrate and where vacuums can’t reach.
Spraying is useful because most sprays contain an insect growth regulator (IGR) that lasts for 7 months. The IGR will prevent new eggs that fall into the environment from surviving. Look for the ingredients pyriproxyfen (Nylar) or methoprene (Precor).
The adulticide (to kill adult insects) in sprays isn’t as useful. It will kill new adults that emerged from the environment. But adults only make up 1-5% of infestations, and most live on animals. To make matters worse, adulticides has a relatively short duration of activity.
Since the IGR is the most important active ingredient, and it lasts 7 months indoors, you shouldn’t need to keep spraying. Regular vacuuming should be sufficient to remove and kill the newly emerging adult fleas.
While new generations won’t be able to take hold, many of the fleas already living within carpets will likely escape spray treatments and vacuuming. These immature stages need to mature, emerge as adults, and die before the infestation ends. So, it is not uncommon to see new fleas emerge, even with proper treatment in place.
You may have a continuing problem with untreated cats hanging around your place. They likely have fleas. And each female flea lays around 25 eggs a day. The eggs are laid on the host, but aren’t sticky and fall off within a few hours. Eggs could continue to be dropped around your property, and the infestation could continue.
Cat fleas (C. felis) shouldn’t infest the guinea pigs. They aren’t a preferred host. It would be rare to find one on a rodent, but still it’s not impossible. Regardless, as far as I know, cat fleas shouldn’t be able to survive on guinea pigs. Rodents have their own species of fleas, which also typically don’t infest cats or dogs.
I hope this helps!
Adam