They are a HORRIBLE thing.... my niece has them in her apartment and just had it sprayed for the 3rd time. It has nothing to do with how clean/dirty you keep your house - they love it anywhere. It is a complete nightmare to prepare your home to be sprayed and you have to get rid of furniture that is infested. She is extremely allergic to them and has been fighting a terrible rash and finally discovered them in her apartment. I feel so bad for her - all I can say is wash in hot water if in doubt.