Dust mites are tiny arthropods that can be found almost everywhere. They live in house dust and their excrement is the number one indoor allergen. A protein in the fecal products and disintegrating body parts of these miniature mites is the substance that adversely affects those who are sensitive to it. Dust mites are impossible to completely eliminate from living quarters. They have sticky pads on their legs that enable them to burrow into many household items, like furniture, and resist even the most powerful vacuum cleaners.