It can take a while to erradicate a full blown infestation of certain types of fleas. It may also take a lot of work cleaning, washing, spraying, vacuuming, and repeated efforts. Persistance pays off. Never surrender, never yeild, and never give into the fleas, or they will drive you insane. I tend to get them bad here in February through April, but it varies from year to year.
As you have done, spot-on treat the cats with Frontline or Advantage. I have used both, they both work fairly well. I have tried a lot of others and they do not seem to work as well. If you have a REALLY bad infestation you may want to treat the cats every 3 weeks (that's what my vet recommened to me last year). They both will kill fleas, flea larvae and flea eggs. This time of year I can go 5 weeks between treatments for my cat, unless we are exposed to them somehow.
Keep yourselves from bringing home even more fleas. When they are bad around here, they are at the stores too, especially places like Home Depot where people tend to take their dogs (I do not know why they allow people to bring their flea infested dogs to those places, but they do). Note that a minority of people are actually allergic to flea bites, and many people are covered with them and do not even know it. I spray myself with Off with DEET before going to town when fleas are bad here in the spring, and I carry a can of it in the truck in case I am hit by them at a store or public place. Visits by friends can also bring them into the house, especially if they have untreated dogs with them, or flea infested pets at home.
Someone here mentioned Borax, and that kills fleas. I use a few TB of Borax in every load of laundry, and that will kill any fleas that are on your clothes. It works, and it is pretty cheap for the results that you get. Vacuum everything and spray the bags with flea spray.
Bomb the entire house, and use a bug bomb made specifically for fleas that has Precur in it. That is a growth regulator that prevents imature fleas from developing into adults. I also use Hartz yard and kennel spray that I mix in a floral sprayer and I spray the outside areas of the house, like the patios, deck and especially the door mats. That stuff lkills all stages of fleas, including the eggs. It is strong stuff, and you need to avoid the areas that are sprayed until it dries. I also use a flea spray called Enforcer Flea Spray for the home and I spray it on the stripped matress, furnature and corners of the rooms where fleas tend to hide. That stuff kills all stages of fleas and their eggs, which you have to kill in order to prevent a future infestation.
Basically you have to completely nuke the little bastaids. Its total war, and I have to do all the above to keep them in check if I get an infestation here. When I bought this house it was completely infested with fleas, as the previous owners had a micro-mutt and it had a lot of carpets. Fleas can go and remain dormant for years, and they will wake up when they feel vibrations. Then they hop around looking for a host to feed on. I bombed the house with industrial strength bug spray, but that only worked on the fleas for about a year. I thought that my cat was brining fleas into the house, but it was the dormant fleas in the house the first year, along with the infested mice that were getting in from the yard. Then it was me that brought them home this year from shopping at a big box store that was riddled with them. I was getting bitten so much I left the store and complained to the manager on the way out. I sprayed with DEET in the parking lot and I washed my clothes as soon as I got home and showered, but that was not enough. I left a trail of the evil creatures wherever I was that day, and it took me a few weeks to erradicate them. I avoid PetCo like the plague. That place is always infested with fleas. I get most all my flea stuff online, as it is a lot cheaper than at PetCo and the like, and the mailwoman does not have fleas.
There are also a wide variety of fleas out there, some 2,000 types in all? The most common (and somewhat tolerable) are cat fleas. They are a nuisence but they are controllable. There are other types that I call 'nuclear fleas.' Get a few of them on you and within a week they are driving you mad with bites that itch like mad. Likely they are a type of human flea (there are several). Most flea species are rather selective as to what species they like to dine on, but they will all pretty much bite any warm blodded animal that they come in contact with to see if they like the buffet. My yard seems to be full of deer fleas in late summer when they come around to dine on my gardens. I put up deer fences last year around my berries and so far they have avoided my yard this year. For some reason I do not get tick bites. Fortunate for me, my ex was a tick magnet and we would walk in the woods and we would have to do a full body check of her when we got back to the house. I never had one on me that I was aware of, but usually she would have 3 or 4 crawling around on her or starting to dig in for dinner.
Good luck with your war. Never give up, never surrender... never become dinner.
