The harmful effects of powder mites on skin include enlarged pores, increased oil secretion, increased dandruff, itching and folliculitis. 1. Enlarged pores and increased oil secretion: powder mites can stimulate hair follicles after invading the human body, resulting in the enlargement of hair follicles, blood vessel expansion, and promoting sebaceous glands to secrete a large amount of oil, resulting in enlarged pores and an abnormal increase in skin oil. 2. Increased dandruff, itching: mite excretions can stimulate the sensory nerves, causing itching; when the mite draws nutrients from the skin, it can accelerate the aging and damage of the skin cells, which will lead to dandruff and skin damage, and will also deteriorate the skin, and the skin color is dull and yellow. 3. Folliculitis: powder mite stimulation of the skin will cause skin damage, triggering the inflammatory reaction of the skin, leading to the occurrence of folliculitis, so that the skin appears erythema, papules, nodules and other manifestations. If the above symptoms appear on the skin, you should go to the hospital in time to clarify the cause and follow the doctor’s instructions for treatment.