Over-the-counter aerosol foggers are ineffective against bed bugs because the mist from such foggers does not penetrate the places where bed bugs usually hide, such as under mattresses and inside carpet. Even when the mist reaches bed bugs, the bugs are often resistant to the toxins used in foggers.
The majority of over-the-counter foggers contain pyrethrin and pyrethroid chemicals. Unfortunately, most bed bugs have built up a resistance to pyrethroid chemicals due to overuse of the chemicals by consumers in an attempt to eliminate bed bugs.
Signs of a bed bug infestation include live bed bugs on mattresses and bedding, rusty-colored blood spots on mattresses and bedding, and the presence of a sweet-musty odor.