Allergies occur when the immune system overreacts to substances that are typically harmless, known as allergens. Common allergens include pollen, dust mites, pet dander, mold spores, and certain foods. According to the Asthma and Allergy Foundation of America, more than 50 million Americans experience various types of allergies each year. The symptoms can range from mild, such as snee... https://greenwoodairductcleaning.com/