How can fleas live in a vacant house for 4 months? They are infested.
If you read our Flea Control article, you’ll learn that flea pupae can live for up to a full year no in a vacant home with no problem. And since they’ll only hatch when there is a food source close by for them to feed upon, anyone entering a vacant home which has lots of flea pupae will be subject to an immediate attack. I suspect this is what you’re experiencing at this time.
Flea Article: www.flea.net/flea-control.html
So if you want them gone, you’ll need to follow the recommendations listed in our article.
As explained, the fleas won’t die naturally until they hatch because the pupae will protect them from chemicals, the environment, etc.
And the best way to get them to hatch is to install Flea Traps throughout the home. Once in place, you must visit the home as often as you can (at least once a day would be ideal). During such visits, walking throughout the structure will get the pupae hatching and if you move quick enough, you should be able to avoid being bit. And once you leave, the ones that have hatched will then target the traps. Additionally, moving the traps every 2-3 days around the home will get pupae hatching too as the traps will be perceived as a sleeping pet.
I also recommend treating every rug with the Once a Year Flea Granules and then spraying over the top with Permethrin 10. You can do this every other week until the problem subsides.
Permethrin 10: http://www.bugspraycart.com/insecticide/liquid/permethrin-10
Pump Sprayer: www.bugspraycart.com/good/pump-sprayers
Lastly, spray any hardwood or tiled flooring with Precor 2000 every month until the problem is gone.
Precor 2000: www.bugspraycart.com/insecticide/aerosol/precor-2000