An allergen is any substance that can trigger an allergic reaction. The immune system recognizes allergens as foreign invaders and mounts a hypersensitivity reaction against the harmless substances. There are many common indoor allergens that generally cause only minor symptoms such as red and itchy eyes, runny nose and skin irritation.
House Dust
House dust encompasses a wide variety of particles that can lead to an allergic reaction. These fine particles float in the air or build up on surfaces. They can come from pets, plants, skin, hair, fabrics, and food and waste particles. Dust in the home is inevitable, regardless of the frequency of cleaning and dusting, but can be controlled and limited. However, the amount and type of house dust is highly variable depending on factors such as age of house and type, temperature and humidity, and the number of people, pets and plants in the home.
Dust Mites
Dust mites, relatives of the spider family, are microscopic bugs that eat the dead skin cells shed by people. Common and found in most homes, they generally take up residence in beds, bedding, furniture, carpeting and material made from cloth. They can number in the millions in a single pillow or bed. They thrive in warm, humid environments and can only be seen through a microscope. Although unavoidable, they can be reduced with frequent washings using hot water, dust mite plastic coverings for bedding, and reducing household temperature and humidity.
Pets
Pet allergies are quite common to animals such as dogs, cats, hamsters and gerbils. Contrary to popular belief, it's not the hair that people are allergic to, but rather the particles of urine, saliva and dander, or dead skin flakes. However, pet dander quite frequently collects on pet hair and thus is spread through a home by this manner. Some people are affected by all types of pets, while others only by specific breeds.
Molds
Two common types of fungi that grow indoors are mold and mildew. They live almost everywhere, but indoors they take up residence in damp areas such as bathrooms, kitchens and basements. Allergic reactions stem from mold spores inhaled from the air when mold and mildew is disrupted. It is important to check for leaks or water buildup in a home to prevent the development and spread of mold and mildew.
