In a recent study of dust-mite allergy sufferers, one group slept on mite-proof bedding, while a control group slept on bedding that was not mite-proof  The group using mite-proof bedding had a 69 percent reduction in the dust-mite allergen in their mattresses, whereas there was no significant reduction in the control group
However, even though bedding is the main source of exposure to dust mites, no symptom reduction was reported in either group
For dust-mite allergy sufferers to get relief from their allergies, dust-mite allergens must be reduced by 90 to 95 percent.