There is no known way to prevent allergies . Symptoms may sometimes be prevented by avoiding known allergens.
Mold spores are everywhere.
Stay indoors during summer and fall, when mold is most prevalent. Use synthetic fabrics for clothing and household furnishings whenever possible. Disinfect bathrooms, basement walls, and furniture with diluted bleach or other appropriate disinfectant solution. Dust exposure is minimized by frequent cleaning. Vacuum frequently, preferably using a small-pore filter to capture dust mites.